Terminal Arrival Areas

I always try to improve on the processes that I have.  Whatever it is, I like to analyze the process to complete the job and then find ways to optimize it… make it better, more effective and cost effective.  The same goes with the airlines, who above all else, want to cut costs.  They know that staying at altitude as long as possible is more fuel efficient than coming down on multiple steps far away from the airfield.  If the airlines had their way, they would glide from their cruising altitude all the way to the runway with engines at idle.  It is possible, the technology to make this happen already exists and the FAA is coming along with RNP type approaches.

One of the steps the FAA made with the former in mind was to create terminal arrival areas for standard GPS approaches.  The big thing here is that GA aircraft will take more advantage of this approach than any other aviation operation.  The idea is the same, ATC will clear the aircraft, sometimes from the cruising altitude, for the GPS approach.  This allows the aircraft to descend when they want to make the approach.  It is quite a cool thing.

The GPS approach into Vero Beach above shows a terminal arrival area.  Notice the “T” approach design.  There are IAF fixes at each of the three points.  Once the FAA clears you for the approach the “free flight” concept relies on the pilot to maneuver as necessary to enter the approach at the given IAF at an airspeed and intercept angle to correctly fly the approach.

How does it work, once cleared for the approach the pilot can elect to descend down to the TAA altitude within that section of the approach.  For example, if you are west of HOCHI intersection, once you get within 30 NM of HOCHI you can descend down to 2000 FT MSL.  Imagine cruising along at 8,000 MSL and ATC clears you for the approach.  There are 6,000 FT to lose and at a standard 3° descent will take 18-20 NM. 

Obstacle clearance is also taken into account.  The TAA from the NE has a step down arc.  Most likely, there are tall antennas to the NE of the airport.  Not that big of a deal though, plan to stay above 2700 till you are within 25 NM of MRINO intersection.  I have also seen notches in a TAA section with a radial and DME arc to define the notch.  The arcs cannot be within 4 NM of the fix or within 4 NM of the TAA boundary.

For more information reference AIM 5-4-5(b) or FAA Order 8260.58

2012 in review

Here’s an excerpt:

4,329 films were submitted to the 2012 Cannes Film Festival. This blog had 29,000 views in 2012. If each view were a film, this blog would power 7 Film Festivals

Click here to see the complete report.

Stick and Rudder

I read a lot of aviation blogs, on email lists and such.  This particular email came from Thomas Turner of Mastery Flight Training in early November.  If you would like to subscribe to his newsletter, please do so, it has some great content.  He had a reader chime in which he added to his email that I wanted to quote.

This week’s FLYING LESSONS features frequent Debriefer, airline pilot and general aviation enthusiast David Heberling as a guest columnist. David sent me this email in response to last week’s discussion of angle of attack and spin awareness following an engine failure immediately after takeoff. He’s sent it to other aviation outlets also, but I think David’s comments should spark a good conversation here as well. David writes:

I realize it may be hard to believe, but I just finished reading Stick and Rudder by Wolfgang Langewiesche. I have to credit my wife for bring the book home from the library. She wants to understand flying better.

I have read many flying books and magazines during my 40 years of flying, but I have never had it presented quite like it is in this book. I actually learned something new. The primary message of the book is that the elevator directly controls Angle of Attack of the wing ONLY. My training spoke only of “pitch and power” being the totality of our flying experience. It is easy to understand why he hammers at this theme. Too many loss of control accidents occur as spins out of turns.

Langewiesche presents many examples of spins out of steep turns, the engine failure scenario being one of them. We also know about the take off and departure scenario and the base turn to final one as well. He attributed all of them to pilots cheating with the bottom rudder to quicken the turn. This cheating leads to a cross-control situation and high angle of attack. It is the attempt to raise the low wing that gets them into trouble. That the aileron can cause the section of wing ahead of it to go beyond the critical AOA is something I never thought of. The surprise and puzzlement must be extreme when the low wing goes even lower instead of rising. The spin soon follows and time is running out.

All of this cheating with the rudder was a revelation to me. I have never ever thought of doing the same thing myself. Coordinated turns were pounded into me relentlessly during my extended student pilot pre-solo period (3 years, from 13 to 16). Now, I understand why airline upset training wants us to PUSH first (unload the wing/reduce AOA), then roll level, and power as necessary. Now I understand how pilots spin out of turns. I have tried it in my aircraft at altitude. All I ever achieved was a very high pitch attitude and a turn so steep it made me dizzy. It is not the turn itself that causes the problem, it is the attempt to return to level flight when turning all cross-controlled.

This book was written in the 1940s. Everything talked about in this book is still true today. Pilots still spin out of turns. Why have I never heard about this in aviation safety circles until reading this 1940s book? Langewiesche talks about how pilots are poor judges of AOA, especially in a turn. In our airplanes, we do have a handy AOA indicator. It is the yoke. You could actually color code the shaft if you wanted to. The first half could be green, the next third could be yellow, the last couple of inches would be red. The green would be closest to the control wheel, the yellow further out, and red next to the panel when the yoke is fully extended.

I find it incredible that today we are wringing our hands over the stuck value of GA accident rates. We are all agog over scenario-based training to solve this problem. Back when this book was written, the author and Leighton Collins thought that rudderless (no rudder pedals) were the answer to this problem. This idea has never caught on in any appreciable way and I can understand why. I do think Leighton had the right idea about exposing students to this phenomenon. Yet, this never happened. Where do we go from here? How do we bring AOA back into the forefront of training? How do we inculcate students against cross controlling (except in crosswind landings) and cheating with bottom rudder in turns? How do we demonstrate this exact scenario so the student can see how you can actually stall just a portion of the wing (an extremely important portion at that) and cause a spin?

Maybe FLYING LESSONS is not the place for this kind of discussion. Do you know a suitable place? I would like to participate in it wherever it happens.  – David Heberling

How many times have we disagreed on the concept of pitch control what and power controls what?  My very first flight instructor taught me that pitch controls airspeed and power controls altitude and then I was handed off to a different instructor at the same flight school and he quickly learned that I was doing it wrong.  For the next $1000s of dollars I spent, I had to unlearn what was primarily taught to me (remember the law of primacy) and learn the “correct” way the school wanted that concept taught.  I can still hear the second instructor yelling at me that I was told incorrectly and need to get it in my head that power controls airspeed and pitch controls altitude.  No exceptions.

After earning degrees specializing in advanced aerodynamics.  I believe there are situations where both sayings are correct.  You simply cannot adjust one variable without the other variable changing as well.  This is why I like David’s comments so well.  If we would simply realize that the elevator controls the angle of attack of the wings only, both of those methods will no longer matter and the training industry can move on from these arguments.

Think about it, on the backside of the power curve and holding altitude the slower you get the more power you need. The only way to increase airspeed is to lower the nose.  Since we realize the airplane is at such a high angle of attack, by reducing the elevator (and angle of attack) we can regain flying speed.