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A good pilot is always learning right?  Well, I have learned something recently about TAA approaches, procedure turns and how they are charted, especially on the Jeppesen charts.  To begin, let’s take a look at this traditional RNAV / GPS approach:

This is a standard “Basic T” approach that uses a Terminal Arrival Area (TAA) to assist with the transition from the enroute structure to the terminal environment.  You can see how this approach has the  3 standard IAFs (initial approach fix)i to guide you to the intermediate leg, which is the approach leg located between the intermediate fix (IF) and the final approach fix (FAF).  In this case, DEHYY serves as both a IAF and the IF.  If you given DEHYY as your IAF, you will either have to fly the procedure turn (PT) or NOT fly the procedure turn based on your arrival area.    Since the procedure turn is drawn with a black bold line, we know that it is a charted published portion of the approach, again only if the requirements for flying the procedure turn are met.   You’ll notice that if EBEKY or GIMMU were your IAFs, then you are not to fly the procedure turn as it very clearly states in the plan view “NoPT”.  You’ll also notice that in the “straight-in” area that there are two segments or step downs that are defined by the distance to the IAF, in this case DEHYY.   There is a 30 NM, 3100′ segment and a 8 NM, 3000′ segment to DEHYY in the straight-in area.  I have highlighted this straight-in area in yellow on the approach plate above.

I was on a very (very) short reposition flight to airport that was located about 10 miles away from my departure airport.   After takeoff I climbed up to 3,000 feet (my initial and final altitude) and almost immediately after my initial contact with departure control I heard the words “Cleared direct to DEHYY, maintain 3,000 until established, cleared for the GPS RNAV Runway 28 approach.”  Ok, no big deal, I’m doing the full approach on my own.  I loaded the approach in the FMS and proceeded direct to the initial approach fix (IAF) of DEHYY.    Like I said, this was a short flight and I was pretty busy with the after takeoff, descent and approach checklists.  Never mind that I had to double check my Vref speed, set the VNAV minimums in the autopoilot and obtain the latest weather on ASOS!  I had just enough time to glance down at my Jeppesen approach plate and read the notes associated with using DEHYY as the initial fix.  I saw the “1″ and “2″ and quickly determined that because I was at 3,000 feet and within 8 miles of DEHYY, the procedure turn IS required because I don’t see the words “NoPT” like I did see for the 30 miles and 3100′ transition or the north (GIMMU) and south (EBEKY) transitions.  I WAS WRONG!

I started the procedure turn outbound and heard approach ask, “Are you headed eastbound?”  “Yes,” was my response.  All I heard as a response initially was quiet….that’s not good.  “Ok, call us inbound”  “Roger”, I replied.   “Oh, and if you wouldn’t mind please calling me when you get on the ground too”  Oh boy, that’s definitely not good.

Make a long story short, after calling approach and contacting the Jeppesen charting office, I learned something very important about how transitions and procedure turns are charted. When there is a common transition to a fix, the “NoPT” is only added to the first leg of the transition. (please read that twice).  For instance, if you look at the above approach plate, you can see that the words “NoPT” are placed next to the 3,100′ and 30 NM transition but not to the 8 NM and 3,000′ portion.  Although it is not explicitly stated, the procedure turn is NOT authorized for that leg of the transition as well!  Did you know that?  I sure didn’t.

Now that some time has passed and I’ve thought about it, it makes a lot of sense that I didn’t have to do the procedure turn.  However, at the time, all I knew was that I didn’t see the words “NoPT” beside my transition, so I thought that the procedure turn was required.

I took a look at the NACO chart for the same airport, and to be honest, the NACO chart makes it a little clearer that a procedure turn within that 8 mile, 3,000′ transition is not required but it leaves some room for question.  Here is the same approach:

On the NACO chart you can see that “NoPT” is added for that entire straight-in transition area (187 ° through 007°) and by the way that it is drawn it does a little better job of implying that that procedure turn is not to be flown while in either steps of this transition (3,100′ and 3,000′).

Do you know when else you are not required to do the Procedure Turn?

1) When the symbol “No PT” is depicted on the initial segment being used

2) When receiving radar vectors to the final approach course

3) When conducting a timed approach from a holding fix

4)When ATC specifies in the approach clearance “Cleared Straight-In (type) approach”

5) When a teardrop procedure turn is depicted and a course reversal is required, this type turn my be executed.

6) When a holding pattern replaces a procedure turn, then the holding pattern must be followed (unless you meet one of the above rules)

7) When the procedure turn barb is absent from the plan view

These limitations all come from FAR 91.175 and AIM Chapter 5-4-9.

Here is the summary (which is also explicity stated in the AIM):  Anytime you have any question about whether a procedure turn is to be flown you should “immediately request clarification from ATC”. I could have saved myself a lot of grief (and some time & fuel) by just taking a second (despite my workload) to say “Just want to clarify, are you expecting me to fly the procedure turn?”   You should never be so busy as to not have time to request a clarification from ATC.

Well, I hope you learned something from my mistake and that it keeps you from doing something similar.    I’ll be honest, I don’t like confessing when I’ve messed up (even though I do it all the time) but I really hope that at least one other person comes away from this having learned something about procedure turns and how they are charted.

Fly Safe!

With Paul’s recent post on the VFR day and night equipment mnemonics, I figured it would be a good opportunity to start collecting some more. If you’re working on your Instrument rating, you’ve probably wondered if there are any mnemonics for the IFR required equipment dictated by §91.205.

GRABCARD is the classic memory tool:

• Generator or alternator
• Rate of turn indicator (turn coordinator or turn & bank indicator)
• Altimeter, sensitive (Kollsman window)
• Ball (inclinometer, the ‘level’ component of a turn coordinator or turn & bank indicator)
• Clock (digital display or sweep second hand)
• Attitude indicator
• Radios as required for navigation and communication
• Directional gyro or heading indicator

Of course, the applicable VFR day equipment always applies as well, and if you’re flying IFR night you’ll need the VFR day and night equipment.

Have you got alternate mnemonics for any of the §91.205 required equipment? Let us know in the comments and we’ll add them!

Charles, a 2000+ hours ATP asked the following:

“Hi, I have a question about GPS approaches. Why are LNAV and LNAV/VNAV minima different on RNAV GPS Approaches?”

Great question Charles. Things are changing so fast in the GPS world that it’s hard for instrument pilots to keep up with all of the new acronyms and just what they mean. But you want to understand them before you’re stuck in the clouds, furiously twisting knobs, while hoping to avoid an encounter with a cumulo-granite cloud (Ouch!).

I’m going to be self-serving–since it will save me a lot of typing–and quote directly from two of my books and CDs. Many readers may not be familiar with LNAV/VNAV minimums for a GPS approach, so let me quote from my new Max Trescott’s GPS and WAAS Instrument Flying Handbook (which I might add would be a great Christmas gift for pilots to buy now for themselves!):

“As previously mentioned, airliners with special equipment fly to LNAV/VNAV minimums and now you can too with a WAAS-capable receiver. From a practical standpoint, however, you’ll probably use these minimums only on the handful of approaches for which no LPV minimums are designated, since LNAV/VNAV minimums are almost always higher than LPV minimums. In very rare cases, LNAV/VNAV minimums can be lower than LPV minimums, due to differences in how obstacles are evaluated for these approaches. So surprisingly, a GA pilot’s WAAS-capable receiver that can fly to LPV minimums is far more versatile than many airliners’ equipment, which cannot go lower than LNAV/VNAV minimums. Like LPV minimums, LNAV/VNAV minimums are specified with a DA or decision altitude.”

Charles, you wanted me to contrast that with LNAV minimums. Let me briefly explain to readers that LNAV, which stands for lateral navigation, is the tradition minimums to which we’ve always flown GPS approaches. Originally there was only one minimums type for a GPS approach, so those minimums didn’t need a name. Now that there are 5 different minimum types available for GPS approaches, the original ones needed a name so they’re called LNAV. LNAV minimums are basic, non-precision minimums. Just fly to the MDA (minimum descent altitude) specified and don’t go an inch lower than that altitude!

Now we need to know how what pilots call the “protected area” differs for LNAV/VNAV and LNAV minimums. This time let me quote from the audio track of one of my computer courses, Max Trescott’s WAAS and GPS CD-ROM Course (another great gift idea for a pilot to get him or herself for Christmas).

“Let’s talk briefly about the protected areas for LNAV/VNAV approaches. First, the horizontal protected area is the same as that used for constructing a LNAV approach, so the equipment required to fly these approaches only has to meet the TSO-C129a, which is the standard for non-WAAS capable receivers. Since the navigation will therefore be less accurate, larger protected areas are needed than for an LPV approach.”

Now we know that the horizontal protection areas are the same for LNAV/VNAV and LNAV minimums. So essentially your question would be identical to “Why are the minimums different between an ILS and a localizer approach.” The answer is of course the glide path (or in the case of an ILS, the glide slope). Non-precision approaches resemble the steps in a flight of stairs and pilots can immediately descend down to the next altitude at each step. But the glide path of a RNAV (GPS) approach more close resembles the handrail for a flight of stairs. It provides a smooth, continuous descent path. The glide path can be designed to avoid obstacles that might force a higher MDA for a non-precision approach. So the answer to your question is that LNAV/VNAV minimums are usually lower than minimums LNAV minimums since it incorporates a glide path, helping it avoid some obstacles.

Kent wrote me this morning asking:

While flying recently with my friend a question came up which has come up for me several times in the past. I firmly believe that while flying VFR practice approaches (as published) into an uncontrolled airport that radio communication with the controlling ATC needs to be made-I always thought the approached as published is their approach. My friend firmly believes that as long as it’s VMC and uncontrolled airspace that one does not need to be talking to ATC. I do agree that it seems to be common practice to fly these on your own without ATC but is this really appropriate/legal?

Hi Kent,

This might be one of the cases where what is legal isn’t necessarily safe. The safe thing is always to contact ATC and request flight following / radar services when practicing any kind of approach.  Remember, that’s why they are there (and for now it’s still a free service). Even if you aren’t receiving radar services it would be prudent to at the very least monitor the appropriate frequency.  The reasoning of course is that if an airplane comes along that really does need to shoot that approach (corporate, airline, etc), your presence on the approach might make the required IFR separation difficult if not impossible for ATC.   Also, having that second (or third set) of eyes is always a good backup in case both pilots become preoccupied with the technicalities of the approach.  How sad would it be if ATC could have stopped the collision of 2 VFR aircraft…if only they were talking to them!  That brings up another point too, what if there is another aircraft on the same approach that has a pilot with the same mentality of your friend?   Now you have 2 VFR airplanes, practicing the same approach and neither of them are talking to ATC…that’s just asking for something to happen!

However, according to the AIM Chapter 3 Section 2, in uncontrolled airspace or class E (as I’m guessing your approach is in) there is no communications requirement for VFR aircraft.   I find nothing else published saying that you have to establish contact with ATC just because you are on a segment of an instrument approach.   Technically your friend is right but that doesn’t mean that would be the safest operating practice (I’d rather be safe and alive then dead and right).

As a pilot (and PIC) you have every right to stand up for yourself and establish your own operating procedures.  Let everyone you fly with know that your rule is to contact ATC on VFR practice approaches.  Don’t let yourself be lead down the path of least resistance!  A good pilot listens to his gut. If something doesn’t feel right, STOP!  Don’t continue.  Figure out what you don’t like about the situation and correct it.  If you don’t like practicing approaches without contacting ATC, then don’t do them!  There are plenty of times in my career where I’ve had to stand up for a situation I thought was unsafe, even if it was “legal” to continue.

Fly Safe.

Jim is working on his Instrument rating and spotted an interesting approach procedure:

Not surprisingly, an ILS approach will have lower minimums that a non-precision approach, such as a localizer. However, I have found at least one airport in my area where the localizer MDA (580′ MSL, 564′ AGL) is lower than the ILS DA (743′ MSL, 727′ AGL). I’d like to understand why this is true and under what circumstances I can anticipate a lower minimum for a localizer than the ILS.

Jim is talking specifically about the ILS or LOC/DME Rwy 24 approach to Bowerman Airport (KHQM) in Hoquiam, Washington. There’s an interesting (if not completely confirmed) story behind this approach in particular, but before I get into that I’ll cover the basics.

With this approach, as with any ILS, the FAA must certify that no obstacles penetrate a predetermined gradient. This means that even at full-scale glideslope deflection, there is a built in buffer between your airplane and the ground below. If terrain or an obstacle (buildings, trees, antennas, etc) sticks into the approach path, then the FAA has two options: the minimums (ceiling and visibility) for the ILS will increase, or the glidepath angle (currently 3° at KHQM) must be increased to clear the obstacle.

With the localizer-only version of the approach, you can descend to the MDA of 580′ once past WIMET (D3.0 from the localizer). The additional distance fixes on the localizer approach permit a pilot to descend past the obstacle and land safely. Unfortunately, to answer the second part of Jim’s question, there’s no way to predict the inversion in approach minimums unless you’re intimately familiar with the airport and the surrounding terrain. The real answer is to make sure that you thoroughly brief each approach before flying it.

The specific details about Hoquiam are after the break! Read the rest of this entry »

Has this ever happened to you?  Sometimes, you just look at a mechanical part and think, “I wonder what’s inside that?”  or maybe you ask yourself,  ”How does this thing exactly work?”  Pilots by nature I believe are pretty inquisitive creatures.  For us, surface or book knowledge alone does not suffice.  We want to personally know and understand what makes things things “tick”.

I had the privilege recently of helping an aircraft mechanic as he took apart an alitmeter.    Why did we need to take it apart? Well, we had no good reason to take apart the altimeter, we just wanted to.    The really impressive thing here is not that we took it apart…but that we got it back together!  And it works….well, sort of.

Read the rest of this entry »

Before Takeoff Checklist
Throttle: 1700 RPM
Magnetos: Checked
Carb Heat: On
Carb Heat: Off
Throttle: Set-800 RPM
Flight Instruments: Set
Takeoff Briefing….huh???

A common problem that I see in many of my students (both primary and advanced) is the failure to adequately brief the takeoff and departure segments.  This is a critical and common mistake with many pilots.  Richard C. Cushing summarized the importance of planning when he said:

Always plan ahead. It wasn’t raining when Noah built the ark.

This quotation really summarizes the purpose of a good takeoff briefing.  A takeoff briefing should clearly state your plan-of-action for both when everything goes as planned and “when it starts to rain”.    Because as the proverb says:

He who fails to plan, plans to fail

So then, what should you include in a takeoff briefing?  I think a good takeoff briefing is one that answers questions. Questions like:

• Who will perform the takeoff? Student or Instructor?
• Which runway are you departing?
• What type of takeoff is going to be performed? Normal, rolling, short field, soft?
• What will I do if I lose an engine during the takeoff roll? What about a engine loss at 50 feet? 500 feet?
• What are the critical V speeds for this particular aircraft? Vx, Vy and Best Glide.
• What are the departure instructions? Is there an obstacle departure procedure that I need to be aware of? Does my departure clearance include a SID?
• Which airport would I go in case of an emergency and the airplane was still flyable?  Sometimes the departure airport isn’t prepared to handle an engine fire or has a runway long enough to deal with a complete hydraulic failure.

Do you see now the importance of including a pretakeoff briefing before each and every flight? This is not a procedure just for the first-flight-of-the-day.  A takeoff briefing should be performed if you’re staying in the pattern, departing on a cross-country and with or without an instructor present.  Every takeoff is unique and each requires a different course in the case of a malfunction.  It should also be noted that a verbal (as in out-loud) briefing should be performed in both single pilot and crew pilot configurations.  Just because you don’t have a pilot sitting in the cockpit listening to you doesn’t make the exercise without merit.  Verbalizing and listening to your own voice through the intercom / headset is a good way to solidify and commit your intentions to memory.

Here is a a sample takeoff briefing that I would use in a single-engine aircraft:

This will be a normal takeoff.  We will departing on runway 24 with an initial altitude of 3,000.  Vr is 50 and Vy is 67.  If we have any problems before rotation or with adequate runway remaining after liftoff, we will abort.  Standard emergency procedures will be used in the event of engine failure without adequate runway remaining.  Best glide is 65 KIAS.  We won’t even think about returning to this airport unless we are at 1,000 AGL.  Any questions or comments?

As you graduate into more advanced aircraft, you’ll notice that your takeoff briefing will have to be adapted to match the performance of that airplane.  For instance, here is a sample takeoff briefing for a light jet aircraft:

This will be a rolling takeoff with flaps set at 10 from runway 23.  We will abort for any reason below 80 knots.  After 80 knots we will only abort for engine fire, engine failure or  failure to maintain directional control.  After v1 we’ll handle it as a in-flight emergency and continue the takeoff roll.  Memory items will be as required and hold all checklists till 1,000′ AGL.   If we have to return, we’ll request a left downwind for 23 and pattern altitude is 1,500′. Departure instructions are the Airport 5 SID which has us making a left turn to 210 deg at 500 feet.  Standard calls. Any questions?

I’ve provided these as a basis for you to develop your takeoff briefings.  I’ve warned you about the dangers of not using a pretakeoff clearance but there is also a danger in “rote” recitation where you can just say the words, without really giving them the thought they deserve.

I don’t have to rehash the accident statistic rates here, but I’m sure you know how a large majority of aviation accidents and incidents occur during takeoff and landing phase.  That is why it is so crucial that we plan for a emergency before they happen.  Playing defense against an emergency, without a clear cut plan, is much harder than playing an offensive maneuver that has been rehearsed and discussed.

Fly Safe (and brief those takeoffs!)

This is a question about a question!

Pilot Mike writes:

Thought I’d throw this one over your way to see what your thoughts are. Hangar flying this question has yielded several different answers from both IR pilots and CFIIs… You are departing an airport on an IFR flight plan; the route is “direct” to your destination. Upon climb out, ATC gives you radar vectors around arriving traffic at another airport. After about 15 minutes away from your filed route, ATC asks, “What is your on course heading?” Which heading do you provide back to ATC? Some different answers I’ve been told: 1. The heading direct to your destination from your present position 2. Heweeading to intercept your original filed route. 3. The original on course heading as filed. What is the appropriate response to ATC?

The appropriate response to give ATC is your heading that you would need to fly from your present location to the fix as specified in ATC’s request.  Why would controller need this information?  Well, I forwarded this question to Paul from FAAfolies.com and here was his response:

There are a variety of reasons the controller might need to know the heading; you’d think it doesn’t matter since the a/c has direct nav capability but it might be to see what the winds are, or there might be traffic to parallel, or other reasons.

I also called my local approach control facility and their answer was that many times the destination or next fix is defined to ATC in terms of lat/long coordinates.  You can only imagine how difficult it would be for a controller to know the on-course heading difference to a place that is 39N 34 55 versus 40N 05 10.

So what I do when ATC asks me? Well, to be honest, I just normally look at my GPS or FMS PFD and find the BRG or DTK field:

The course in that field, is the number I usually respond to ATC with.  Any technically it isn’t a “heading” and it doesn’t help ATC know what the winds aloft are but I haven’t gotten any complaints yet.  Again, the feeling I got from ATC was that they are just looking for a general idea of which way your going to turn to proceed to that fix.  If they need left or right of that course for traffic sepeartion, they are going to tell you to turn.

Thanks for your question Mike and….

Fly Safe.

This is great follow-up question to a previous post, “Can you use a q-route below FL180?”. The question came to me after posting a link to that post on my Twitter profile.

So what the heck is a Q-route?

Well.  There are primarily three types of airways:

1) VOR Federal airways – This is the airway system that most pilots are most familar with.  This includes your typical low alitudes “V” airways and the high-altitude “J” routes.

2)  Colored Federal Airways – There are still 49 of these airways still in existence.  LF and MF and they can be found mostly in Alaska.  They are designated by their color names Amber, Blue, Green or Red and then either a one or two digit number, i.e. “A 7″

3) RNAV airways – This is the latest and greatest route system found in our nation’s airspace.  The foundation of the RNAV route system started in 2000 with industry operators requesting the FAA to increase the use of RNAV to help navigate the nation’s airspace.  The advantages of the RNAV system?  Reduced mileage, reduction of conflicts between routes, and additional routes within the same airspace.

There are two types of RNAV routes:

1) Q-routes (high) are available for use by RNAV equipped aircraft between 18,000 feet MSL and FL 450 inclusive. Q-routes are depicted on Enroute High Altitude Charts.

1) T-routes (low) are available for use by RNAV equipped aircraft from 1,200 feet above the surface (or in some instances higher) up to but not including 18,000 feet MSL. T-routes are depicted on Enroute Low Altitude Charts.

So now a good follow-up question would be, “Can you file and use a Q-route below FL180?”  and you see, we the staff at askacfi.com have thought ahead and already answered that one for you and you can read the answer to that question here.

David asked the following:

“Hi, I have a question about Q-routes. I understand they were developed for class A airspace. However, the Q100 airway out of Tampa, Florida has a 6000 foot MEA and a 1500 foot MOCA. Can you use this airway assuming you have /G and say fly at 7000 feet on an IFR flight plan?”

Great question David. So great that it took some research and phone calls to the FAA! As background for readers, Q-routes and T-routes are relatively new types of airways defined by GPS waypoints and requiring an IFR-capable receiver. They were created to handle the increasing density of air traffic and to take advantage of the widespread availability of GPS. T-routes are low altitude airways and Q-routes are high altitude airways. Per the AIM, Q-routes can be flown as low as FL180.

Q100 appears on a low altitude en route chart, which normally is used only for navigating below 18,000. So that begs the question: Why does a

Q-route, which can only be used above FL180, appear on a low altitude chart which is only used for navigating below FL180? I didn’t know, so I called the experts, the FAA’s RNAV/RNP group. They thought it was a very good question too. Which is why they had to make 3 phone calls to find out–and they’re the experts!

The answer back was No, you probably cannot get a clearance to fly this route even if you filed for it, unless you were flying above FL180. The reason it appears on the chart–at least for now–is that it was one of the first GPS airways, and it was created before the altitude rules were established (in 2003 as I recall) for T- and Q-routes. Thus it’s a legacy, which doesn’t really belong on the chart. But now that you’ve asked us and we’ve asked the FAA, don’t be surprised if it disappears from future charts. So save your current chart. It may become a collectors’ item!