Ask a Flight Instructor

Posts Tagged ‘IFR’

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.

Lance asked:

“Can I do my instrument currency approaches, hold, and intercepting a radial in an aircraft that is not IFR certified? Such as a DA-20 with Garmin 530, so long as I’m in VFR conditions with a safety pilot? Thanks!”

The FARs are permissive in the sense that if something is not prohibited, then it’s allowed. Here’s my interpretation. 91.205 (one of the few number I know by heart) specifies what equipment is required for IFR flight. You said you’ll be in “VFR conditions” which I interpret to mean that you’ll be flying VFR in VMC conditions. Thus, your aircraft only has to be equipped for VFR flight.

61.57 (c) states what experience is required to act as “pilot in command under IFR or in weather conditions less than the minimums prescribed for VFR.” It talks about the 6 approaches, hold, etc. required during the prior six months. It says that experience must be “performed and logged under actual or simulated instrument conditions, either in flight in the appropriate category of aircraft for the instrument privileges sought or in a flight simulator or flight training device..”

You can certainly simulate instrument conditions in a VFR aircraft. Thus, you could get your instrument experience in an aircraft that’s certified for just VFR, as long as don’t fly IFR, remain in VMC conditions and bring a safety pilot who’s rated in the aircraft and has a current medical. One minor point, while doing this, if you ask ATC for a clearance to fly approaches, make it clear that you’re requesting a “VFR practice approach.” Otherwise, you’ll be treated as an IFR aircraft, which is not permitted if you’re not instrument current. If I’ve requested one but am “cleared for the approach,” I’ll readback “cleared for the VFR practice approach” just so it’s clear to everyone that I’m not IFR.

I received an outstanding question this afternoon concerning instrument approach visibility minimums from Michael.  His question went something like this:

I’m looking at the RNAV (GPS) Z Runway 31 at McNary Field in Salem, Oregon (SLE) and I can’t make sense of the minimum visibility requirements of the approach.   Why is it that the visibility requirements for the LNAV only are so low?  On this particular approach the required visibility for the LNAV only is 2400 RVR or about a 1/2 mile.  That doesn’t make any sense!  I wouldn’t be able to descend from a MDA of 940 with only 1/2 mile of visibility!  Can you help shed some light on it?

Like I said mentioned before Michael, great question.  Let’s take a look at the RNAV Z RWY 31 approach into SLE.  For those who are interested, you can view a copy of the approach plate from EchoPlate:

Maybe at some point we’ll go over the terms and definitions of this approach plate a little more throughly, but for now, I’m going to try and just answer your question about the confusing visibility requirements.

Why are the visibility requirements so low for the MDA on the LNAV only approach?

The reason is the differences in the physical location of the Missed Approach Point (MAP) between the different approach types authorized for this approach.  Take a look at the MAP for the LNAV only approach and then compare it to the MAP for the LNAV/VNAV approach.   I have highlighted in red the locations of these two different MAPs in the illustration above.  For the LNAV only, the MAP is basically the start of the runway.  If you reach this MAP without having 2400 RVR AND you don’t meet the requirements of 14 CFR 91.175 then you must begin the missed approach procedure.  For the LPV approach and the LNAV/VNAV approach, the MAP corresponds with the DA which is most likely going to be physically further from the runway thus the higher visibility requirements.

Now you bring up an interesting point about the practicality of this approach.  Let’s say you are at a MDA of 940 and suddenly you have the airport environment and the required min. visibility, so you should “chop and drop” in right?  Well, let’s read 91.175 again.  14 CFR 91.175 says that in order to operate below MDA you have to be:

In a position from which a descent to a landing on the intended runway can be made at a normal rate of descent using normal maneuvers

So it may very well be that you have the required visibility before the MAP and you still have to execute a missed approach simply because you are not in a condition that you’ll be able to make it to the runway surface using safe and normal maneuvers.

I hope this clarifies things for you Michael.  If you have any other questions, feel free to comment on the this post and I’ll do my best to find an answer for you.

If anyone else has questions about the terms used in this explanation, feel free to ask me a question about which term you are confused about.

Thanks again for your question and ….

Fly Safe!