Use of PAPI or VASI glide slope for landing small single engine aircraft

Richard Hages on Aug 31, 2010

ounds like you’re pretty set in your ways so i’m not sure this is going to help you no matter what we say. First off, there’s no faster way to get a CFI angry at you and to make your flight training less enjoyable than to argue with him. It’s like a dish washer in a kitchen arguing with the head chef about how to make dinner. It doesn’t make much sense. The 3 degree glide slope is not based on engine out glide distance, but based on obstacle clearance. One thing that you learn during instrument training is how the terminal procedures are designed at each airport and how the glideslope must maintain a certain amount of clearance to any obstacles while approaching the runway. While I would agree that you may not be able to make it to the runway if you had an engine failure at any significant distance out on the glideslope that in no way makes flying the glideslope careless and dangerous. Descending from a high angle which requires a large control deflection in the flare is no less careless or dangerous. When flaring from a high angle you will put more load factor on the aircraft and subsequently raise the stall speed putting you dangerously close to a stall in an already speed reduced situation. Just remember, both your CFI and the Examiner have spent MANY years getting to the point that they are at. While questioning is a good thing, arguing is not. Trust us… please

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Gary Moore on Sep 01, 2010

I gotta agree with Richard on this one – most accidents happen during the landing phase – time and time again the research has shown that a stable, published approach, is far safer than the alternative.
Also – I question the logic of ‘needing to make the runway if the engine fails’ – I’ve heard this concern many times over the years. But well over 95% of your flying has you in a position that you won’t make a runway if your engine fails (unless you exclusively do only pattern work) – so why is it suddenly higher risk in the pattern?

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Thomas Vaillencourt on Sep 01, 2010

AMEN! Great answers both of you guys! Apparantly Christopher Ian’s instructor has not explained what the glideslope is for. Whether visual or radio, the glideslope is there for obsticle clearance. To Christopher, I hope you will move forward with a more open mind, and be more accepting of the teachings. they are there to keep you alive, and flight training has been around for a long long time now. Please believe that the instructor knows more than you do, and read up on hazardous attitudes.

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Dhruv K on Sep 02, 2010

Well hold up guys. In how many places does flying the approach ABOVE glideslope negate obstacle clearance?
As a CFI myself, this has come amongst constant debate at my flight school. In fact, the school’s recent amendment to our stabilized approach SOP has been to eliminate the required adherence to the PAPI/VASI. The new rule is simply that we fly a stabilized approach that will assure a landing within the first 1/3 of the runway or within the established touchdown zone, if one is present.
Furthermore, a stabilized approach doesn’t automatically mean a 3-degree descent. In fact, attempting to fly a single-engne trainer in at mfr recommended approach speeds while holding a 3-degree glidepath puts the airplane WELL on the backside of the power curve, meaning you’re actually using more power to effectively drag a slow and dirty airplane down final. The Aug 2010 AOPA Pilot magazine actually had an article that discussed the risks of such a procedure at great length.
I’ll close with this: Fly the airplane in a way that you feel will safely assure a landing with minimal dramatics once you reach the point of flare and touchdown. If your actions are justifiable and don’t present any undue risk to the aircraft or the environment, you won’t get any argument from me in the right seat if you’re trying to increase your safety margin in case of an engine failure.

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Thomas Vaillencourt on Sep 04, 2010

I am not an instructor yet, so take my friendly advice for what you may think its worth: While there is no actual regulatory REQUIREMENT to fly ON a visual glidpath, as it is sometimes necessary to fly in a manner so as to avoid wake turbulance, which puts you well above the glidepath in most cases.
It is commonly taught and common practice that in the presence of an operable VASI or PAPI, one should always try and maintain the proper indicated glidepath. This can however produce the need for a faster than normal (POH recommended) Approach speed. It is perfectly safe to fly above or on the glidepath, just keep in mind when flying above it more runway will be required for the landing. In short though I would suggest the student should try as much as possible to perform as instructed, which will almost always coinside with what is expected by an examiner. Save your personal flying habits or style for after you are rated, just keep it safe and legal, and you should do well.
With specific regard to focus on possibility of engine failure, while I agree with Gary Moore’s response about 95% of flying being outside the airport environment, thus why the extra risk in the pattern, my thoughts are as follows… True, most of the flying is not in the close proximity to an airport, but also most of it is also at an altitude that (hopefully) offers a few options for emergency landings and time to choose the most suitable one. However, while in the traffic pattern, you are at an altitude that in most cases leaves the runway as your ONLY option, and it would be smart to always maintain a position relative to that runway, that would facilitate a safe landing if the engine were to fail in the pattern.

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AV8 U on Sep 09, 2010

When dealing with engine out landings, you should never be required to fly according to the PAPI/VASI. It should however be required to fly a stabilized approach, which does not mean on a 3-4 degree glide necessarily, and taken on a simulated case by case basis. By correctly setting the airlplane up to ensure a safe landing is made on the runway, considering you can safely make the runway and its your best choice, you can maintain a consistant and stabilized approach. If you however in terms of a practical test are being tested on a situation such as maintaining at least the correct PAPI/VASI indicator due to a simulated obstactle, or some other terrain issues like you can encounter at mountainous airports, then coming in exceptional high can potentially indicate fear of coming up short, which is normal in this given simulated situation, where just making the runway would be your primary concern. But in means of the test it also shows a lack of precision, and a lack of understanding aircraft controllability.
To sum it up, you should be required to maintain simply a stabilized approach to a safe landing to the first 1/3 of the runway. But this is not to be abused by simply coming in EXCEPTIONALLY HIGH everytime, which I have seen, just to slip the aircraft.

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Christopher Ian on Sep 30, 2010

My response > your answers. Thank you for input & replies ~ No sound/sane case exists for flying {most} light planes (VFR) on low 3-4 deg VGSI gpath.
The 1st 3 replies are absolutely scary~ inane, impertinent refs to IFR, instru, CFIs & training, incorrect aerodynamic application & understanding ~ All w/no correct or compelling reasoning to not fly above VGSI gpath. These 1st 3 replies are so bad, my specific comments are in separate entries (if this system permits). As we are in a teaching & sharing environment, I must reply. Feel free to reply to my email directly.
Note: Engine power failure 5 weeks ago-C172M w current CFI. During landing phase.
Background: First 2 CFIs, in CA, Citabria tail dragger (no flaps) taught me keep runway w/in reach at all times in the pattern. Ldg w/Papi – nearby field- shown how the lights work, told- “this in no way indcates you can glide to the rwy on this GS”. Early on, I read lrnd & was taught perils of typical (relatively) hi power, hi AOA, hi pitch, low-gpath angle appr -‘muscle it in’ – ‘hanging on the prop’ type landing. Fly the plane, not the lights. Adjust for crrnt conditions. “Engines are more apt to quit while manipulating eng cntrls”- Thr-Mix-(Prp) w/fuel related cause- just what we do on every lndg. Close proximity to grd necessitates approp cautions.
Flyg power-C172 w glider CFI (cfi#11) for 1st time, patterns, jokingly, “hey- you’re above the g-path”. Reply: “if I fly any lower I won’t make the rwy if I lose the engine”.
These CFIs get it. In aviation we play it for the rare unexpected occurrences. We train for it. We keep our options. We have a plan B (plan C, D & E). I was taught well. Flown & landed 11 ac (3 gliders) & soloed 6 ac before private-glider last month. Logged time w 11 CFIs & 2CFI-Gs. All been terrific – especially the half that comprise women. When a CFI (or anyone) teaches me something- I ask questions. If something seems ‘wrong’ – odd- contrary, I ask.
If it is wrong, I say so. We move on. At least 5 CFIs have said-taught-explained something wrong. Question, discuss, correct & move on. I have seem worse actions on part of CFIs and other pilots than this.
My CFI re: the GS lights agrees we can fly above the GS – bend the rules (there are no rules on this) – seems compelled from exp – on com flt test- last lndg- “chopped pwr & dropped it in”.   Failed. Presumed to be – not stabilized-. (?) Failure was not because – not on GS path- but because not stabilized – as best I can tell. She does not want me to have similar problem.
Flying “the lights”- has warped my sense – my perception of what the ac wants to do- & will do easily & naturally w/its flt characteristics. In the curnt condtns at ech lndg.    I am lrng to fly the lghts- not the ac.      Bad practice.      Fly the ac & cndtns- not the lights.
Teachg or instilling student/pilot fly ON a 3-4 deg gs infers this is correct, proper, ‘safe’, best apprch to lndg in the ac. Not true. Forcing ac fly a pre-set gpath angle opposes normal-natural flght charactics of the ac (& aerodynamics) in any particular conditions – think of elements that chg gpath while flyg. Wind, air density, ac wgt, pwr, spd, turblnc, lift, sink & others.  You insist on flyg (diffrt) gs angle at ech apprch detrmnd by the VGSI lghts. Stndrd ptrn, proper spds & cnfig, (try low pwr), 59degF- 1 ft elev, low humdty. Plane will take a particular gpath angle. Chg any of those elements, your g-path chges – physics dictates this. No choice. But you insist on forcing the same gpath, regarddless.
Best. Day 1. Low ac wgt, cold air>low hum>hi air den, no wind= high ac perf.    Worst. Day 2. 97degF (day I soloed C172) hi hum, W10G24-45deg x-wind, strong lift & sink, max gros ac wgt. You insist ac maintain same gpath angle both days. Foolish.    Both days, I adjust accordingly. I Now ignore the lights. Always. Even with CFI.
Flyg last week- I ignored lights. High(er) angle (above ind GS), same (correct) spds, adjust pwr & cnfig in dif places in pattern. Round out, flare, touch down in nearly identical spots as when on lighted GS. No sig incr in load factor (ridiculous cpmment by Richard)  A myth, incorrect statement (by Thomas V.) more runway is required from a high(er) decent angle. Do your homework- go back to school. You are wrong.
Want to see me land (safely) w 30deg g-path angle? Give me a few minutes, I’ll tell you how strong a wind I need to do this safely. I’m guessing 45-50 kts. I fly final no slower than 60 on final- add 50 kt wind- gs= 10. Measure, triangulate -figure the gpath angle. Vertical spd -descent = 500 fpm -same as always.   A much diff apprch – look & feel.
Fly 3deg gpath-angle, 20kt wind req hi(er) pwr. W max gros wt, thin air (hi temp, hi-hum, lo-press) frthr pwr inc is req 2 maintain gs angle. You apprch & realize a position far down back side of pwr curve as these conditions dictate. Bad practice. You insist in all conditions to fly set-gpath angle. Foolish. Incorrect. Wrong. Fly the plane, not the lights.     As pointed out – VGSI shows angle to avoid obstacles. True & that is ALL it does.   CGSI does NOT show you angle to fly ac – any ac-
VGSI gpath angles differ – betwn 2.5-4.5 degs(w/extremes beyond) . Does 1 ‘size’ fit all ac?- all conditions? Does it make sense to do this or teach it?
Encrgng prac of flyg a GS angle – rather than flyg the ac prevents pilot from lrng what their ac can & wants to do w/low pwr or in glide & how to adjust in diff conditions.    Far better practice- learn spot lndngs & consistency.  Learn to choose and land on a spot every landing regardless: of wind or conditions. Do it w/ no claps. Full flaps. Power. No power.    Avoid use of grnd lndmrks as ref points for the pattern – learn to judge angle frm grd to plane & adjust pattern, spd & elev accordingly- as we do w/ gliders. Your grd track will chg w/ wind & other conditions anyway.   I learned this in pwr 10yrs ago- & started gliders last year.
A 3-deg gs angle = 131 ft alt @ 2,500 ft dist. Lose eng there- “land” 1,190 ft from threshold. A 4 deg=750 ft 5 deg=310 ft. (?) Do you really do this? Think this is high enough or Safe? Do you teach students “this is where you will ‘land’ w engine failure”?   If your student then asks-   is there soemthing we can do to avoid- an engine failure- ‘crash’ by not reaching the runway- do you tell them- “No there is nothing we can do?
Flaps exted =less glide- you land farther away. Do you teach that fact to your students or teach them when & how to retract flaps to extd the glide? If they have enough alltitude ? Most apprchs I have flown (student) this is called a crash.
Flgt trng includes (for me): emerg proc- eng fail, glide to a safe landing spot. Always be looking for safe place to land in case of eng-fail. (taught at age 12 by a P38 pilot).
Eng fail → on take-off run, abeam #s on d-wind, (AFH) discuss eng-fail & 90- 180- 360deg turns to land. CFI-nearly evry flt asks- pwr fail now- where do you land? On Flt Test, if examiner asks this, hesitate a brief 3 or 4 sec- you will fail ! (I am told).
Pilots avoid routes w/no-or limited emerg lndg spots, avoid mtns, water or other terrain that dec safe lndg options. The yadd hundreds of miles to a trip to avoid this. Most avoid flyg over a bay, ocean, lake, mtn beyond a glide to a safe lndg spot. Is there a reason to throw these precautions to the wind during landing phase?
W/current CFI (same one who likes the VGSI) we did 180deg turn back to rwy @600ft agl. In gliders prac this @200ft. Why? To be safe. To insure survival. To keep options!!
All this prep+prac & you are happy & willing to abandon-eliminate option of glide to safe lndg spot-the runway- while you are in the pattern. Why ?
The myth 95% of flying- is beyond reach of rwy- My (3) xc flts @6,500ft- I can glide to a rwy apprx 60% of flt dist (rural NH-VT-NY). Replc ‘runway’ w/”safe lndg spot” -incrs this to 90%+. Safe, prepared, keeping my options. ‘Never give up the runway” i was taught. If i was too low, slow or far from the rwy- and did not correct immediately CFI cut the pwr. “What are you going to do now?” “Uuhhh, turn toward the rwy?” Are you going to make it? Nope. Ok, what is your plan B?
I picture you (or your student)- lndg short, plane toppled over, you survived, plane mostly wrecked in the weeds. Standg at the ‘landing” spot, pointing to pattern descrbg what you did where, turng back to rwy you see > ac owner, arprt mngr, NTSB rep, insrnce agt, (your wife & Mom) all pointing to the 5,200 ft of rwy you missed. Who will be stndng by your side to say, “yes, but he was on the GS” ??? No one.
Logged time w 13 CFIs- 2 had this notion flying ON the GS. CFI#13 on Sunday-back in tail dragger again- I asked her – she said, “irrelevant” re: flying Vasi/Papi. Nothing is written anywhere to support this practice. Not the POH, FAR, AIM, Phak, PTS, AFH. Nothing. The impetus stems from pilots/CFIs flying IFR & instr procs walking it back to small, light ac VFR flying. I don’t just think this is unnecessary. I think it is wrong. Unsafe. Teach this to students – it is negligent. (especially if you do NOT tell them- fly this way- you will not make the rwy- just want you to know that).
My ques. has no refs. to IFR-instr proc & none is implied. VFR, small light ac.   The online discussions re: IFR- instru they tell of flying above, below- whatever is needed in their ac. My CFI- same one- tells me she flies the Citation under the GS to get it in. Hi perf-fast ac are diff – aerodynamically and re: to perf. They also say- once they visualize the rwy – lights- VGSI- they are now flying VFR- not IFR. At least until they must do missed apprch- and at point the VGSI is meaningless- they are flying right past it.

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alfadog on Oct 01, 2010

Got this discussion on a Google search wondering why anyone would want to fly 3% in a C172. CFI’s also teach chopping power “when the runway is made”. Why? Upsets the approach, steepens the entry, increases control forces needed and increases chances of a bad landing. I bought Bransom’s classic “Make Better Landings”. Went out and shot a dozen. What a difference! Set power, speed, flaps opposite numbers; turn fairly close-in base, set flaps and speed; turn final, set flaps and speed, one adjustment to power as needed after turning final; 400 feet 1/2 mile out (that from an AOPA article); round-out level somewhere under 50′ and slowly pull power; plane slows then when sink begins start the hold-off. Above the lights (PAPI, VASI) every time (400′ at 1/2 mile = 9%) and down where I want. Could also make it in the unlikely case of loss of engine.

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Christopher Ian on Oct 01, 2010

Reply- to Richards comments (Aug 31-2010)   Your reply is perplexing. From a CFI it is alarming. You offer no sound case for flying this gpath indicated by the Vasi/Papi lights. Your claim re: a high(er) gpath being careless & dangerous is incorrect at every examination of the aerodynamics, physics (Newtons 2nd Law), practice & common sense. Your ENTIRE statement is incorrect.
The 3deg gpath is based on obstacle clearance. I wonder why you choose to fly & teach a gpath designed to avoid obstacles. Nothing intrinsic in this VGSI gpath directs us to fly -only-that gpath angle. FAR-Sec.91.129 (e)(3) requires flying at or above the (visual) gpath until safety requires a lower altitude. You can fly on-under-above the Gslope. My CFI flies Citation Jet under gpath to get it in. Your ref: g-slope must maintain. . certain amount of clearance . .Yes. Your point would be? 500 feet of clearance above obstacles is what I have read. How does this require we approach ON that low g-path and not higher? You say we ‘may not’ . . “make it to the runway”. . w engine failure”. A low 3deg gpath will insure you do not make it to the runway- no “may not” about it. VGSI 3deg path meets my runway 700ft from threshold. That is the only margin of error I have on your 3deg slope. Measure it- triangulate-engine failure farther than short to mid final means I crash. Not acceptable. For you, this is not careless or dangerous (?). Three of 4 approaches at my field, this is a crash.
Your worst comment re: “descending from high angle . . is no less careless & dangerous”. Best L/D angle is 10:1. We teach this ‘angle’ when engine fails by choosing the correct airspeed (based on ac weight-lower weight we fly slower to get longest glide). You claim “high” angle is careless & dangerous. Well go tell Clyde Cessna (& Piper, Beech, et al & the FAA) their airplanes are designed to be ‘careless & dangerous’ in a power-out glide to a landing. Do you teach & demonstrate emergency power-off (@idle) glides to the runway? This is the Best L/D angle/speed recommended by the folks who built the plane-taken from the POH & required to be published by the FAA. You are stating this angle is careless & dangerous! This is THE BEST ANGLE TO FLY when you lose the engine! Choose a more suitable (pronounced”lower”angle-which you prefer) the ac will NOT glide as far. Basic aerodynamics. Are you just closed-minded? What part of this do you not understand? Geez- you are a CFI!
Next point: “flaring from high angle. . . puts more load factor. . . increases stall speed. .” you are describing exactly what we teach & attempt at each landing. Stall @ slow speed-2 inches above the runway surface. The only improvement would be 1-inch above the runway surface. Newtons 2nd Law. F=m*a. Resultant ‘force’ from a deflection is determined by how fast-abrupt (acceleration) that force is applied. Dive @ 140kts, apply slow gradual deflection until flying level- may result in a 1.1g-load factor. The arc/path of the ac will be large. Dive @ 80kts, apply the fastest deflection you can manage, result might be 1.5g-load factor (or larger) . Do you know anyone who applies very hard-fast control movements while landing?
If a control deflection in a ‘pull-up’ during round-out to fly level did create a stall, the stall would last only until the relative wind has changed back to less than “critical angle” (approx. 18deg) maybe 1 or 2 seconds-as the ac path changes to fly level over the runway and high relative wind/AOA has decreased. You won’t even know the ac has “stalled”.
C172 full flaps stall=40kts. I fly final no less than 60kts. I need to increase stall speed by 50% to stall (yes, I know my ac speed is decreasing at this point)- that increase would = a force of 2.24Gs! For comparison: The (Gs) needed to stall this ac would = a turn w/ bank angle of 63.5 deg (while holding altitude). G=1/cos(bank angle). Cos 63.5= 0.4461. Therefore: 1/0.4461=2.241Gs. (increase in) Stall speed=sq root of G (load factor). Sq root of 2.2411=1.497. Stall speed 40ktsX1.497=59.77kts. If I fly at 60kts, I have not stalled this ac.
You claim this”high” angle of descent (10/1 glide ratio-about 5.8 deg) is careless & dangerous (it is not!), increases load factor (yes it does), dangerously close to a stall (incorrect). Apply control deflection to create a force= 2.24Gs (!!)-> raising stall speed by 1.497, stall speed will increase to 59.77kts. If your round-out over the runway produces 2.24Gs, you need to lay off the caffeine, get a new job, a new wife or just take up boating !
You omit another important aerodynamic factor. Ground effect. We teach: to NOT round-out (to fly level) above ground effect (for me, flare =increase pitch-nose up to hold ac of the runway as long as possible as ground speed decreases). Only w/ my research into this question did I discover a table that shows the relative force of ground effect as a factor of the height (wingspan width) above the ground. It is a curve similar to the Table (in every book) Load factor / bank angle. Ground-effect is negligible at ½ wingspan height(1.1). Considerable at ¼ (1.5?); high @ 1/8th (or lower) wingspan height. Ground effect disappears below 2 or 3 feet- ask anyone who left the gear up what that last 2 feet feels like. My C172-high wing can not ever appreciate the full force of ground effect- as low wing ac do.The increase in effect from 6 ft to 3 ft is significant.  You mention this ‘approaching stall’ at ‘already reduced airspeed’. Ground effect increases lift-by lowering induced drag requiring less thrust (power) to produce/maintain airspeed. Aircraft performance is increased. This effectively makes a stall less likely as we enter & experience the full force/benefit of ground effect. It does not matter that our (lower) speed/AOA ratio is close(er) to a stall. That is our goal on every landing. While landing: Do not round-out high. Do not fly slow. Do not apply sudden-fast control deflection. I think we all learned that in the first few lessons.
Your statement re: approach at “high” g-path angle is incorrect. Completely. By the aerodynamics. Physics. Common sense. Go up to altitude (3k?), fly a descent @ 6deg- 60-70kts. Round-out & tell me about the ‘wicked’ stall you experience. It won’t happen. And no- Thomas V (3rd & 5th replies) is incorrect. This will NOT require higher than POH approach speed or longer roll out distance. My g-path angle is steeper. Speed is the same. Touch down point is the same! Roll out distance is the same. I reduce power& apply flaps in different places. If my CFIs can teach this to me- and I can do it-w/out difficulty-violating safety-& staying within speeds-guidelines- & PTS- how hard can it be-?
Re: CFIs- It sounds as if you get testy or are offended if someone questions what you are teaching. You might expand your definition of the word “debate”. Debate, discuss, reason & even argue- do not equate to- angry. You take it there on your own. If something seems odd- wrong- I will question & discuss. Anytime. Especially if it involves safety. I question to get feedback & information so I can better understand – in this case- this notion of flying the VGSI lights. Most (CFIs, pilots)I have talked to agree flying the lights (VFR -small light ac-C172) is irrelevant. Two of 13 CFIs I have flown w have taught this. No one- anywhere has presented a sound case for doing so- including all replies here. Everyone who has supported this notion- fly the lights- low g-path angle- has referenced instrument approaches.
My CFI has no other supporting case for flying the lights than to say- “we should practice flying as we will in faster higher performance ac down the road( Incorrect- we should fly the ac we are in now), engines are reliable – rare for an engine failure (she has had 2- one w/ me 5 weeks ago-I have had 2 (unplanned) tow-rope releases-gliders & 1 engine failure in lss than 1 year), ATC can vector as all around the airport where we cannot reach the runway (so we should abandon all safety procedures? in the course of approaches?).   Our engine failure turned out OK. Bad news- we were on her low g-path determinedby instrument in the ac- on the ILS runway w/ no Vasi-Papi. Good news- engine failed after touchdown- quick stop w brakes- for back-taxi – low power-near idle- apply throttle- NOTHING. Took us 5-6 minutes to get power back.   Had this occurred 12-16 seconds earlier- we would have been into the 80 ft embankment that descends to the Interstate. On my-high(er) g-path we would have ‘coasted’ to the runway. A Waco – biplane pilot landed on the Interstate a few years ago after turning 90deg left off mid-short final. He did it during the day. We would have had to do it at night.! This was 9:30 pm- dark night-no moon. Night requirements-fullstop landings. As I turned base to final- I STARED at that black hole- the tree-lined-steep embankment – telling myself- ‘got to make it over that black hole!”   5.200ft of runway beyond. 100 ft steep cliff before. Take your pick.
When you, Thomas V. and Gary M. submit such unreasoned, misapplied, ignorant and incorrect statements, conclusions and opinions- you should expect to get slammed. Thomas V. does not seem to know what he believes- having walked his 1st reply back 180 deg after reading a more sensible-thoughtful comment from Dhruv K. You- and I- take on a responsibility in presenting our views and statements in a public forum. W CFI after your name, the responsibility increases. It is one thing to mention a preference or discuss a method you use – even if it goes against regs or might increase risk or have some other effect. Something else entirely to make statements that are factually incorrect. My points, statements, numbers, information are not from my own ideas – but from books and sources- and I offer them to support my opinion re: this notion of flying the lights – maintaining safety- and absorbing- accepting- understanding what our CFIs are teaching- and questioning- and challenging when it opposes common sense, the facts and what other CFIs have taught.   Thank you for reading this far -and for the discourse.

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Wesley Beard on Nov 11, 2010

As a CFII, I teach my students to fly on the glidepath. I typically find that most students have a difficult time determining what glide angle they are on and the lights help cement in what a standard approach looks like. After awhile, when the VASI’s or PAPI’s are OTS my students will still be able to fly the correct approach path. I also prefer to keep my patterns in tight in the *rare* case of an engine failure but also have alternate landing sites selected in the case I need it some day.

With that said there is nothing wrong with flying a higher than standard glidepath as long as the PIC can make good landings. FAR 91.129(e)(3) states the PIC must stay at or abve the glidepath in Class D airspace. This also applies to Class C and B airspace as well. If an examiner fails an applicant because they are high on the approach I would ask where that is found in the FAA literature. Most likely though, they will pass the applicant and have a discussion afterwards.

Speaknig of these higher than standard approaches some things need to be figured out. The higher approach has more potential energy to dissipate than a lower approach meaning the PIC will have to carefully manage the dissipation of that potential energy into kinetic energy. Some techniques are there for short field landings where the A/S is much lower than a normal landing. My best guess reading this thread is that you want to keep as much total energy as possible to allow that excess energy to carry you to the runway. The only thing that I would caution is that you are never going to be able to make the landing distance numbers specified in the POH. These numbers are predicated on a known total energy, so to speak. I remember once landing flaps up and flaring at 100kts in a C-177. I made a super soft landing just landing about 5000 down the runway. Nothing wrong with what I did, but could never make the landing numbers. My advice, if a short landing is necessary due to LAHSO or a short runway, flying above the GS or fast on the approach is insane.

Transport Category airplanes sometimes have a steep approach modification allowing them to fly upwards of a 6degree glideslope to airports like London City in England. In the LR-45, there are quite a few limitations in place if the PIC chooses to conduct a steep approach. Some of these limitations include operational autospoilers, anti-skid systems, nosewheel steering, dry runway with no icing conditions and no tailwind at a max field elevation of 2,000ft. I think we can see that the limitations are designed to keep total enegy to a minimum and once touch down to quickly dissipate it. This is just my $.02.

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Andrew K on Nov 23, 2010

Why handicap ourselves and our students by only using one school of thought? Why not both?
I think, from a training point of view, both pattern styles have their own benefits at certain stages in training.
When the student is just beginning to learn approaches then we’ll setup out on a long straight in approach and get them to use the VASI so we’re not rushing things. This gives plenty of time to learn how to control and configure the aircraft to make a nice stabilized approach with the VASI to augment their perception of glide angle.
Then we work on low approaches without landing to practice precisely controlling the plane at a low speed near the ground and judging aircraft height near the flare. Then after a few trys then we land it.
As the student gets more comfortable and proficient then we’ll work on bringing the pattern in closer until it’s dead stick.
This way the student gets a feel for how diversely patterns can be adjusted to put them where they want on the runway.
On a humorous note see Mr. Bertorelli’s “A Sarcastic View of Pattern Flying” http://www.youtube.com/watch?v=f6q2VKsvQEQ
His video on coordinated turns is good too “When the Ball Just Won’t Behave”
These videos are also why I recommend everyone take at least a couple of glider flights, because in a glider you have to tame the plane with the rudder and have to make dead stick landings. It can be a very valuable experience.

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Micah on Dec 07, 2010

Christopher, I’ve not read everything you’re written (you’ve written too much to be useful to the reader) but you seem to be a very good student of the text. Are you a good student pilot/pilot? Do you learn from the experience of others. You may be correct that you should not fly by the visual indicators, but can you fly a stabilized approach? Does your flying meet the PTS? It may be indeed that you know more than your instructor; neither of you wins by you trying to prove it. Prove to him/her that you can fly consistently or safely. What does the PTS say about flying the visual glide path?

B. TASK: NORMAL AND CROSSWIND APPROACH AND
LANDING (ASEL and ASES)
NOTE: If a crosswind condition does not exist, the applicant’s knowledge of
crosswind elements shall be evaluated through oral testing.
REFERENCES: FAA-H-8083-3; POH/AFM.
Objective. To determine that the applicant:
1. Exhibits knowledge of the elements related to a normal and
crosswind approach and landing.
2. Adequately surveys the intended landing area (ASES).
3. Considers the wind conditions, landing surface, obstructions, and
selects a suitable touchdown point.
4. Establishes the recommended approach and landing configuration
and airspeed, and adjusts pitch attitude and power as required.
5. Maintains a stabilized approach and recommended airspeed, or in
its absence, not more than 1.3 VSO, +10/-5 knots, with wind gust
factor applied.
6. Makes smooth, timely, and correct control application during the
roundout and touchdown.
7. Contacts the water at the proper pitch attitude (ASES).
8. Touches down smoothly at approximate stalling speed (ASEL).
9. Touches down at or within 400 feet (120 meters) beyond a specified
point, with no drift, and with the airplane’s longitudinal axis aligned
with and over the runway center/landing path.
10. Maintains crosswind correction and directional control throughout
the approach and landing sequence.
11. Completes the appropriate checklist.

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Kent Shook on Dec 14, 2010

Well – The FAA seems to think that using the VASI is a good idea. From AC 61-47A:

“The Federal Aviation Administration recommends that all student pilots be introduced early&in their flight training to the use of any available approach slope indicator, and taught to use it regularly in planning standard, uniform landing approaches. The use of uniform-approach angles and descent rates is important to the safe, efficient operation of modern airplanes, especially in congested airport traffic.”

So, why does the FAA say this? The recommendation probably comes from statistics – There are many more accidents caused by landing with excess energy than there are accidents caused by engine failures in the pattern. Being lower on the approach allows you to better manage that energy using power, whereas the “always within gliding distance” can leave you with excess energy despite being at idle. That is why the FAA recommends a partial-power, stabilized approach.

Now, this is one of those arguments in aviation that I find silly. There is a happy medium here, folks – If you don’t buy the “use the VASI” philosophy, try this one on for size: There is a glide path that allows for an airplane with the flaps up to just barely make the runway threshold with the engine out – We’ll call this the “low path.” There is another glide path that will allow an airplane with the flaps fully extended to glide to the runway with the engine idling. Call that the “high path.”

Now, if you fly the low path with flaps – You’ll need some power to make the runway, and you can perform the FAA recommended “partial power stabilized approach” – And if your engine dies, you should be able to retract the flaps and still make it to the runway. Realistically, you would need to be slightly higher than the low path to allow for reaction time as well as allow for a slight temporary nose-down to pick up a bit of airspeed if you need it. Somewhere between the high path and the low path is the place to be. Recognize, however, that this ideal glide path is going to be different for every airplane type and situation.

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John D. Collins on Jan 24, 2011

I find this a humorous thread. The 3 degree approach was introduced to enable the Century series of fighter jets to be able to fly the ILS approach. It still allowed power to be used on the approach, while a steeper approach required too little power and too much speed to maintain a stabilized approach and a shallower approach provided less clearance for obstacles. Over time, it was adopted as the standard for ILS and most VASI and PAPI. In our piston aircraft, most can maintain a stabilized approach with power at approach angles of 6 degrees or higher. In my Bonanza, a power off approach will have a descent angle close to 8 degrees, so I still must carry significant power if I wish to fly a 6 degree approach.

If an airport only supports aircraft with approach speeds below 121 Kts, the descent angle on an instrument approach can be as high as 4.2 degrees and for aircraft with approach speeds below 81 Kts can have an approach angle as high as 6.4 degrees. The bottom line is that the 3 degree standard for most approaches is to accommodate the flying characteristics of jets, not our light piston aircraft. In fact, in the last few years a version of the A318 passenger jet had been approved for flying steep approaches (up to 5.5 degrees) into airports like London City airport in the UK.

The VASI or PAPI provides valuable information to aid the pilot’s judgement on establishing a safe descent angle and at night, it provides terrain clearance when you can’t always see the obstacles. You don’t want to fly the approach below the VASI or PAPI, but steeper angles of descent can be just as safe and have other advantages. For example, a steeper approach is more accurate if you want to hit a specific target for touchdown. It also provides a better view of the runway. As long as a reasonable amount of power is required to maintain a shallower approach angle than required for a power off landing, a stabilized approach at 1.3 times VS0 is possible adjustment of power available to control the descent rate.

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Brian on Jul 27, 2011

John says, ” the 3 degree standard for most approaches is to accommodate the flying characteristics of jets”

Touche John. I’ve been waiting for someone to counter what I believe to be just as humorous as yourself. In fact, I’d go as far as to say that teaching a visual student to use primarily instrument procedures severely inhibits that student ability to learn some very important visual gliding skills. Such as how to judge one, which is probably the single most difficult visual skill for any pilot to asscertain.

To give a little background about me, I didn’t understand what I’m about to explain until about 400 hours (150 dual given) when I started reading basic books like “Stick and Rudder” and “Takeoffs and Landings”. Further, I attended what was once considered a prestigous college flight program. While I believe the training I attained was wonderful in virtually all aspects, it left large gaps in understanding many basic, and fairly simple, visual cues available to me. Let me explain and apologize ahead of time for the length of the subsequent explanation.

Have you ever noticed that, when looking at an object at some angle, that object appears streched? Increasing or decreasing the viewers angle will vary the amount of elongation an object exhibits. This phenomina is the basis upon which a pilot can learn to visually judge their glide path. Interestingly, focusing on the runway numbers gives the pilot a great reference point to judge their path with the use of this concept. Especially if the numbers include 2,5, or 8. In my experience it is easier to notice the streching of these numbers than say a 7 or 1.

The above lends itself to the usefulness of picking one item to begin learning this phenomina. However, keep in mind that all objects in the pilots field of vision can be used, such as the entire runway (and this is why sloped runways are said to obscure our judgement of the glide path). This is because our angular view is changed by runway slope, and with it, our perception of the glide path.

It is quite a shame that it took 400 hours for me to discover this. Especially since I knew of this phenomina existed long before ever stepping foot in an airplane, but nobody ever said, “hey Brian, look at this!” Instead they said, “white on white blah blah blah..”

Ok so now we have a starting point, but there is one other big item that must be addressed. How else can we tell if we are remaining on a constant gliding path? The answer is that everything in the windscreen is moving, albeit very slowly at typical approach speeds, except for the point where the aircraft is going to impact the ground. That point of impact on a stabilized approach will remain stationary assuming no change in pitch is actuated by the pilot. Learning to ignore these ultimately necessary pitch changes is one reason judging the glide is so difficult to see for the first time.

Unfortunately, this is the portion of learning to judge a glide that is so incredibly difficult to learn the first time around. The first can get you started with your judgement, but learning to see this really nails it all home and will drastically improve any pilots judgement of an approach. There are a couple caveats to this later judgement that are worth mentioning:

Slower flight slows object movement.
Stress reduces perception.

Each of the above will make recognition of the stationary point (where we hit the ground) harder to recognize. For this reason I like to have students imagine a box around the numbers and put that as their stationary point. The rest of the time is spent trying to learn to make this point stationary and recognize when it is not. Along with, of course, combating stress and attempting to keep the student as relaxed as possible. One way to do this is for the instructor to do a few landings and verbaly explain what is being seen while purposefully deviating from glide path to give a complete demonstration. Showing only a perfectly stable approach does not give a complete demonstration, how to see and correct deviations is just as important.

One final option, however, is for the instructor to fly a stabilized decent at some high speed while at altitude. Since this increases the rate at which all objects, except the point of impact, move up or down the wind screen it can assist in helping the student see it for the first time. This can create some fun competition as well. Say we start at 3,000 agl and fly 120 knots till 800 agl. Along the way the instructor and student can debate about what point they will hit the ground. Something that won’t easily be seen by either when high up but will become quite prevelant as you decend below 1,500 feet.

Well that wraps it up, familiarize yourself with these two visual cues and your perception of glide path will be everything it needs to be to fly a perfect approach every time.

Finally, to the instructors here, in my humble opinion it would do the student a far greater service to make the focal point of early landings being proper judgment of the glide path without the use of unecessary aids. After this basic visual skill is attained (and it will take the better part of 20 hours to perfect for most) PAPI/VASI approach information can be taught in a one hour night lesson.

Happy flying everyone!

~Brian

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Brian on Jul 27, 2011

Thomas said, ” just keep in mind when flying above it more runway will be required for the landing.”

I am sorry to call you out Thomas, but this is a fundamental conceptual error. In fact, a steeper glide path is exactly what is required to land on the shortest runways over tall obstacles.

Only two items, ignoring mechanical and environmental factors, change the landing distance: approach speed and approach angle. The later only effects landing distances when an obstical must be cleared where as the preceeding effects landing distance directly all the time.

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David Eberhardt on Dec 14, 2011

here’s my 2 cents … I have a few hours experience so I practice a variety of pattern techniques. I will fly sim eng out glides in a Cherokee 140 where the rate of descent is usaully around 1000 feet per minute. Not a problem handling the round out and flare. I also practice this eng out stuff with a variety of flap settings. I also practice 3 degree glidepath using power, casue I practice flying ILS approaches to mins and landing from it, so I maintain that 3 degree glidepath to the glide path point of intercept on the runway (which is farther down the runway than the aim point I use for VFR patterns).

I like steep approaches and use the runway numbers as my aimpoint usually. I like steep approaches just because they are good practice for getting into airfields where a steeper approach angle is desireable. Not that worried about engine failure in these modern times. If you fly a steep approach the VASI will show high at first, then on glide pth, and then eventually to below glide path.
I use VASI and PAPI guidance at night for added safety margin.

I think students should learn to stabilize on VASI until they display the ability to judge descent angels later on.

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Jack Dander on Jan 16, 2012

VERY interesting subject. I just would like some real world numbers to think about before my next flight lesson. Any help is appreciated. Here goes: My CFI wants me to be 1/2 mile from runway, 1000 ft AGL, on downwind and reduce power opposite the 1000′ mark on runway. Using NM, that means 1000′ to end of runway on downwind, 3000′ to base turn, 3000′ to final turn and 3000′ + 500′ to landing aim point on runway. Total of 10,500′ at 1.4 Vso and then 1.3 Vso. So, 1000′ AGL in 10,500′ is 5.4 degrees. Not too bad, according to most of the discussion above. At beginning of final I am 3500′ from landing aim point,and 3000′ from runway. If my whole descent was uniform, it would have taken roughly 60 sec to travel 7000′ and reach beginning of final and I would be about 350′ AGL. If I raised flaps immediately there, I could glide 3333′ hypothetically at 6 degree best glide. So that looks pretty safe, too, regarding engine failure. My question is my CFI asks me to do a two step approach, and asks that I descend from 1000′ AGL to 500′ AGL from the beginning of power off above to the point of turning final resulting in a descent of 500′ in 7000′ or 4 degrees. Now, I am left with completing the final 500′ descent in 3500′ which is 8.1 degrees. Here is my question, that starts with a statement: My last lesson was last week, and my next lesson is next week. For a few days now, I searched the WWW and got nowhere about the numbers regarding pattern altitude and distance from runway on all sides and glide slope. Every place spoke of 3 degrees. all the time. One guru said anything above 7 degrees was crazy. (AOPA’s Flight Training Mag for Feb 2012 states 400′ and 1 mile on final is ok, at 3.8 degrees.) Therefore, I was thinking of a way to tell my CFI that he was crazy. THANK you guys for straightening me out before I made a fool out of myself. My question is what is the no-wind best pattern dimensions for a C-172 if the 2 step method above is not already the best.

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Jack Dander on Jan 17, 2012

Another case where glide slope of 3 degrees should be ignored: In my untowered airport, the PA is 1000′ AGL. The standard pattern is 1/2 mile out. If you use SM instead of NM you get 9420′ total distance in the manner described above, so the glide slope if uniform would be 6 percent instead of 5.4 in NM usage above, and it will be higher if you do not begin descent immediately at the 1000′ runway-opposite point on downwind. Furthermore, a 1 mile final could cause you to miss seeing the non-radio regular guy on a 1/2 mile out final turn. Also, note: In my description above, on the two step approach, my descent was 500’/min up till final turn and 1000’/min on final. (500′ in 30 sec). This high rate of descent is called reckless or hot-dogging in many places on the web. (If my math is wrong, Please let me know, as this subject is keeping me awake at night……. thanks.)

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Lake Tahoe Flyin on Jun 03, 2012

Yes, Micah, I believe you have got it. I think Mr Ian has never flown a plane before, but suffers from a John Nash complex.

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Christopher Ian on Jun 03, 2012

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From question originator Christopher Ian:    Interesting treatise on flying, landing, VASI glide path & Regs.   ~>Most insightful reply; student Jack Dander reply #s 18 & 19. >Utterly clueless reply; Lake Tahoe Flyin #20. I do welcome all (or most) replies & a vibrant informed discussion.

! ~Fatality at ‘my’ airport in Feb due in large part to pilot inability to maneuver at low altitude, power out (or compromised) & adequate emergency training & competency. ~>C182 departure on R36, flew 1 mile N, radioed tower stating need to return to field right away. Given clearance on ANY runway (18/36 – 07/25). No further transmissions. Pilot flew back to field, over tower at N end of field from NE to SW, CFI witness stated at around 2-300ft.   Appeared to be on downwind for 36L one- mile away!   Wings rocking & plane yawing excessively, flying at or near stall & 2-300 ft altitude as stated to me by CFI.

Plane flew downwind, turned E onto base very close to threshold, overshot centerline, banked sharply to left, nose dropped, described as stall/spin/crash. Impact 500ft SE of the #s for 36. Wind 6knts,Visibility clear, No traffic. 1 witness described engine failure somewhere. ~> Sadly, inexplicably, pilot flew past 3 approaches (18, 07, 25) two-5,000ft+ runways (07/25 crosses 18/36 300 ft from threshold of 18) and missed landing on 250 acres of flat ground. W/ a compromising circumstance; mechanical (or medical?), pilot flew 1 mile to land from the opposite end of the field.

Whether mechanical or medical circumstances ~ this suggests lack of training & competency in power out & emergency situations. Any pilot could cut power over the tower, glide to & touch down hands-off & survive.

~ This accident relates to my question directly.   Do your students know how the aircraft performs w/power out ? Can they adequately judge an unconventional approach in an instant? Can they void conventional procedures and negotiate a successful, survivable landing including landing downwind? OR, will they approach at a ridiculously shallow angle taught by you as normal, suitable & correct? ~In the glider club we are apt to have CFI or senior pilot fly w/ us for performance check as season opens & pull release at any point forcing us to turn back 180 deg at 200 or 300 ft (no other choice) or more difficult, at 4-500 ft where we have choices & must decide quickly. I have done 180deg turn back at 650ft w/ the CFI I reference who insists on flying the lights & had 200+ feet left to set up for touchdown (C172).

~ I know how my aircraft performs: glider or power; w/engine or power out! I know where I am, suitable landing spots & which ones I can glide to in ALL aircraft I fly at any time.   I judge not by distance, but by angle of declination from my eye to a landing spot.   And you can be sure the angle I choose is NOT EVER 3 degrees ! At 3 deg, I do NOT reach my target spot in single engine aircraft. EVER! Best glide; that is, longest distance (C172) is 6 degrees.   Why fly a shallower angle than that? I have had 2 tow rope releases (unplanned) & 1 engine failure in 2 seasons; all were w/ suitable non-emergency conditions.
<1000ft pattern, ¾ mile wide (likely wider than you fly) is 14 deg. In gliders we fly downwind at distance/ altitude ratio 2/1; = to 26 deg! in an aircraft w/ 3x glide distance of a C172. We never fly at a distance / altitude / glide angle combination where we cannot reach the field. Duh! >When you choose to fly final at VASI/ PAPI slope (3-4deg), you are descending from 18-20 deg slope abeam the #s (1000ft pattern, 1/2 mile from runway= 20deg) to 6 deg slope somewhere on base and continue descending below a safe altitude where you can reach a landing spot (the runway) w/ no power. Why? ~>ANYONE who believes they have to fly a shallow 3 deg slope to be safe (Richard Hages reply #1) is in urgent need of re-training. I fly power at my higher glideslope (6+ deg) & land on the exact spot I land w/ my old CFI flying the lights (3 deg). Airspeed is the same (& within PTS), rate of descent is the same. Go figure?! Do the math, do the physics & do the logic!

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Christopher Ian on Jun 03, 2012

Reply to #20 ‘Lake Tahoe Flyin’ on Jun 03, 2012; “Yes, Micah, I believe you have got it. I think Mr Ian has never flown a plane before, but suffers from a John Nash complex.”
Lake Tahoe; Since you choose to offer nothing in enliightenment, ideas, facts or anything worthy of a reply, I am informed you have nothing to offer. If you have not been paying attention, I am a pilot, power & glider, I soloed more aircraft than could fit on my student certificate & I soloed power & glider 17 days apart before achieving private. Your reply. A vapid effort citing another reply that had something to offer. But lets look at Micah’s reply. Nothing in the PTS suggests an angle for approach. Only reference to airpseed & the vaguely defined term; stabilized apporach. A few POHs mention a suggested approach speed. Otherwise we reference 1.3 Vso (+10/-5). We presume this speed on final as our speed is declining througout the pattern. I do not turn final at 70kts and keep that speed all theway to 10 ft above the runway. Vso = 42 in a C172 I have flown, so speed is 1.3 x 42=55 (too slow for me) w/ range of 50-65 to meet PTS standards. Allowance for wind and gusts broadens this range. Add 1/2 gust factor to approach speed & some factor for steady or strong headwind, perhaps 5, 8, 10 knts. You can achieve increased approach airspeed w power or pitch. Choose the former, your angle coming in will be shallow; the latter, your angle will be steeper. Your airpseed will be identical (if you are a good pilot w/ very good perception). The difference; I use (kinetic) energy (and a little power). You use nothing but power. Lose power, you crash because you are below the slope that glides you to a safe touchdown. I glide home for my $100 hamburger & 2 more years of flying priveleges. Which one of us passed the check ride or BFR? You or me?
~Next time you go up for your BFR or check ride, be sure to tell your examiner that you do not believe reaching the runway is important & that you NEVER plan for emergencies such as power failure, you never spot suitable fields or landing spots when you fly at 3, 4, 5000ft. Tell this examiner that engines & all mechanical devices are SO reliable today that emergency training is a waste of time. Superluous. A waste of the student’s money. Tell him/ her that you teach this to your students (if you are a CFI). Then write me back and tell me how long it was before you failed the test. The failure is not on ability. It is on stupidity.
You might turn your legs of the pattern at the same spot regardless of wind & fly under higher power all the way to touchdown even w/ 12kt wind gusting to 22kts. I shorten downwind leg, fly w/ less power and touchdown at a precise point. Usually the same one I hit when there is no wind. I do not ‘motor it in’ nose high, ass low, closer to stall w/ higher angle of attack AND closer to the back side of the power curve as many power pilots do. This is the most dangerous style of flying/ landing I can think of.
Micah asks questions. Stabilized approach. This means; a steady speed, rate of descent & w/ instrument & more technical landings & jets, a suitable approach angle. This is a relative term. There is no such thing as steady speed or rate of descent unless you have NO wind, NO sink, NO lift. In that nearly non-existent condition, we could trim the aircraft set power to idle (or slightly higher) & glide in to an exact roundout, flare or touchdown point. Instead, we are constantly adjusting any of; speed/ power, pitch, attitude, drag- flaps/ slips (spoliers /dive brakes on gliders) & pattern as conditions dictate. If you do NOT adjust these things in a very good timely fashion & your speed & rate of descent is not ‘relatively’ stable- as best as can be expected w/ prevailing conditions within some level of safety, consistency & precision, you should not pass.
Are you within PTS standards? Micah cites the PTS & says nothing more. Yes, my approach is within the PTS. There is no suggestion of an angle of approach ANYwhere in the PTS. Of 11 paragraphs, the PTS cites only paragraph #s 5 & 9 w reference to any quantitative parameters as to proficiency. Speed at 1.3 Vso & touchdown at or within 400 ft of a specified point.
What does the PTS say about flying the glide path. It says NOTHING Micah.
This is not about knowing more or proving anything. It is about safety, understanding, proficiency. When flying w/ my old CFI at an unfamiliar airport, she suggested- this is where to turn base, and then said, “hey let’s see if we would make the field if we lost the engine”. I glanced to my left to the threshold & in 2 seconds said, “I can tell you already before you pull the throttle to idle. No” I was right. I would fly approach & pattern higher if given my way of doing approaches; I would have turned base sooner at the altitude we were flying as I was taught by my 1st 2 CFIs in CA. After we landed, she said she wodl solo me right there, unfamiliar airport, no discussion, (17 days after I soloed glider) except I did not have my log book for her solo endorsement (Point: the solo endorsement could be written on a napkin- a logbook is not required).
Micah, Yes, I learn from the experience of others. I read the accident reports, listen to good CFIs & pilots- INCLUDING the one I disagree with on this point. I do not crash. I do not land short. I do not fly low on approaches. I know what my a/c is capable of. I learned all this 10 years before I took to gliders. Glider flying reinforces it.
Have you ever heard of Captain Sully? You know what else he flies besides big jets! Gliders! Sully didn’t try to make it to Teterboro or back to LaGuardia. His reply to ATC offering him Teterboro. “Unable” and he put it down as well as anyone could hope, in the river. Three minutes from power out to splash down. Smart. Trained. Prepared. And he knew what his a/c was capable of – power out.

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Al Hayes on Jan 22, 2013

Hi Chris……..In a quest to renew my CFI, which expired in 1965, I started Googling to help me out on an open book test. That is how I came upon your thread. I read your spirited posts with a sense of bemusement, wonder, (wondering why you’re so militant in your stand), and an itch to get my two cents in. So here it goes. WARNING: If your not open to a little constructive criticism, go no further. You’re wasting your time.

Me? I started flying as a kid of 15, Did some service time where I took advantage of AF flying clubs, got out and went to college where the second year was spent flying DC3’s for their non-sked airline. Quite a nice gig, all for college credit. From there it was off to Frontier Airlines (more DC-3’s) then UA in 1964. I retired in 2000, then a year later took a job with NetJets, flying a Hawker 800XP. During this time I have owned a Bonanza, 2 Cessna 172’s, a Twin Navion and most recently a Cessna 210. So general aviation is no stranger to me.

Chris, if I may ask, what is your ultimate goal in aviation ? If it is just recreational, then I’m probably wasting my time, but if it’s professional, maybe you ought to listen, and I’m happy to, pipe in..

I have worked extensively with checklists, crew resource management (CRM), SOP’s. I have a bunch of research manuals sitting in my closet from NASA, and the FAA on the subjects.

Now the following is my opinion only, and you may not see it in any technical manuals.

What do you think is perhaps the finest attribute a pilot can have, especially when when working in a multi pilot environment?

Stick and rudder skills ? Sure, you better have these

Good decision making skills ? Yup..real Important

Good technical skills ? For sure… better know your stuff…airplane, proceedures, etc.

I have flown with pilots just a few pilots who possess all of these qualities, yet fail in the one attribute that has become so important over the years.

A great pilot has to be able to do all of the above, but he/she must also have an ability to get along well with their fellow crew members. This means being able to listen objectively, and communicating overall in a non threatening, easy going manner. That’s what is so important in CRM. CRM is basically a communications course. A listening course, as well as a talking and taking action course. How many accidents were caused by the absence of good CRM is probably not calculable, but it is very high.

You know what Chris ? Nobody likes a know-it-all, and I must say, you come across as one. And that’s not good if you’re aspiring to a career in aviation. You are very good with your technical analysis, and seem to have a real drive for perfection, and that is good.

But you need to look at the bigger picture. Are there more than one way to skin a cat ? Maybe.

I propose that there are more that just one way to safely execute a proper approach and landing in a Cessna 172, and that’s what the respondents to your question were trying to tell you, but you seem adamant about sticking it to them, including your CFI’s.

As aircraft become larger, faster, and more complex, the ways to make a safe approach and landing narrow down. In a 747, ideally you want to be on Glide Slope, on speed, and stabilized from the final approach fix. But even in a 747, in visual conditions you’re allowed to be high, as long as your stabilized and on the proper glidepath at 500′. (That figure goes up to 1000′ in IMC). That’s not something you would ordinarily plan for, but it’s there if you need it. So even in a large transport airplane we have wiggle room. And good thing we do. I’ve needed it before.

Try to stay away from black and white, either-or, when it comes to technique. I asked my mentor UAL captain when I was just a kid, “what do you do if the co-pilot isn’t flying the airplane the way you want ?” he said, “Al, there may be a hundred ways to fly an airplane safely. As long as it’s safe, I let them do what they want. They’re all professionals”

So SAFE is the key. That little conversation 57 years ago helped me thruout my career. Needless to say, this captain was a highly respected guy who people loved to fly with. But he was also a very high calibre guy that set the bar high. That’s what made him great. Great skills, great personality, great confidence: hence a long distinguished accident and incident free career.

People skills are soooo important Chris. Think twice about how hard you come down on those who disagree with you. You may need the help someday from somebody who just may not want to give it to you. Not a good thing. if your still with me, thanks for listening.

Many happy landings ahead

Cap’n Al

PS …At one time, looking way back, at times I was a little “know it all-ish”….how wrong I was

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Alex Censor on Jun 30, 2014

Adding my minor two cents to an already very complete discussion FWIW:

I had the disscusion Christofer had with his CFI basically pointing out that, in my ELSA with its glide characteristics if at most airports I fly the glide slope indicator that if I had a power loss I would probably not make it to the runway. Also pointed out that my aircraft`s inertia is so low that there`s little danger of flaring on the runway at too high speed because of a high approach. Cut the throttle and it slows down as if the atmosphere as turned into maple syrup. 😉
My CFI and the CFI I used for my last biannual review agreed basically that my take had some validity in the case of my aircraft.. An other way to look at it is “ I`d generally rather be a bit high on an approach than a bit low…. it`s a lot easier to lose altitude if I need to than gain it… especially in my kind of low inertia aircraft where there`s little worry about being unable to spill-off excess approach speed.

Somewhat related issue was targeting to flare just past the numbers as standard practice. Of course I had to practice and demonstrate precision on touchdown, shortfield, etc.
But flying into a 9000 foot runway with an aircraft that even if landed poorly rarely needs more than 1000 feet (best case 350 feet , less with a headwind) why “waste“ all that extra runway when I can approach high and flare mid field. Again gives me lots more margin for power failure during approach, and gets me to the runway exit sooner and off the active sooner.

Again both CFIs I worked with acknowledged some merit to this approach strategy for my aircraft .

Chris,
I also have to agree that if your CFI or examiner is persisting in one way of thinking that you after your raising the issue, if you still can` get on the same page with him you`re probably better off to listen to and repeat back what you`re hearing respectfully and thoughfully acknowledge his/her points and diplomatically defer to him/her for now … or get a new CFI.

Alex
Alex

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Use of PAPI or VASI glide slope for landing small single engine aircraft

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