Improving approach angles
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I plan to talk to my CFI about this as well but curious if anyone here has suggestions. My home airport has two crossing runways. Each runway end is elevated above the surrounding terrain. On two approaches there's a road within 200 feet of the runway and on the other two a small river about 100-200 feet off the end of the runway.

What I'm noticing is that I have a tendency to come in high on my approaches and that's resulting in me having to flair pretty hard which in turn means I'm struggling with getting enough flair without the plane ballooning. I mentioned the raised runway and approach characteristics because I think my tendency to come in high is a result of fear of coming in too low. 

So my question is does anyone have good pointers, ideas, suggestions on getting over that fear and getting used to coming in at a lower (more appropriate) approach angle?

13 Replies
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1407 Posts

I'm guessing your field doesn't have any sort of visual glide path indicator, or “VGSI”, which could be VASI, PAPI, PLASI, even AOE (alignment of elements). See the AIM for examples of those with which you aren't familiar.  My suggestion is to find an airport where there is such a device and do a lot of practice approaches using the VGSI and focusing on the visual picture.  Try some approaches where you hold yourself high on the VGSI, and then settle down to the VGSI centered position.  Get a feel for the difference in picture of the runway in those various positions.  Then go back to your home 'drome and work on the picture there with reference to what you saw at the VGSI runway.

Votes

What final approach speed are you using? Difficulty in flairing and floating are indications that it's too fast. When you are too high, you often end up diving and picking up too much speed when you get close enough to accurately estimate your glide path and touchdown point. I watch my touchdown point on final to see if it goes up or down in relation to the top of the glare shield. If it moves up, I add power to decrease descent rate. If it goes down, I reduce power to increase descent rate. I maintain final approach airspeed with pitch control. Power (throttle) and pitch (elevator) interact with one another so changing one requires changing the other although there is usually a lag between inputs. Another possibility is that you are turning from downwind to base too soon. I have a 45 degree visual point about halfway between the trailing edge of the wing and the fuselage that I use to decide when to turn base. A strong tail wind on downwind will require me to turn sooner from downwind to base and maintain more power on final but the movement of the touchdown point in the windshield is still my guide for final approach power.

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Energy management based on visual cues only can result in chasing the aircraft performance.  Before coming up with a way to save and correct each approach, you'll need to first have the baseline settings required to achieve a specific aircraft performance for a stabilized approach.  In order to establish some kind of measurable performance figures first, I would personally try the following with your CFI:

  • At traffic pattern altitude, establish yourself on a predetermined airspeed, flaps + whatever the power setting it takes to maintain that airspeed and altitude on downwind-- no change of flaps on initial descent on downwind; if you change the flaps configuration on initial descent, you may lose track of the aircraft performance as 3 things are changing simultaneously, aerodynamics, pitch, and power.
  • Abeam the predetermined fixed reference point (i.e. Runway threshold); try 60% power-- i.e.) if 2300RPM is the max RPM, 1400RPM; start your initial descent at 500fpm, trim, and note the airspeed.
  1. If it is a fixed pitch propeller aircraft, adjust the throttle to maintain this predetermined RPM.  If it is a constant speed propeller aircraft, adjust the manifold pressure, as it will change without your input throughout the descent.
  2. Turn to your base leg at the standard 45 degree point as you maintain the power setting.  Use 500fpm as a guideline but never at the expense of slow airspeed.  Some airports with rising terrain around the runway will probably need a separate point at which you will turn to the base leg (i.e. altitude).  It is at this point, you will have a good initial perception on your aircraft performance.  With steady power and descent fpm, how are your speed and altitude looking relative to the runway (not the terrain around the runway)?
  3. During a stabilized approach, minor corrections are feasible when you are able to make 2 “trade-offs” in your aircraft's existing energy (speed and altitude).  If you have to change 3 (speed, altitude, and  power), it is a large correction, and your initial “glide” setup needs to be reconsidered:
    1. if it's too fast and too high, your initial RPM setting needs to be reduced the next time around; try 100RPM less, maintain that RPM, and still start with 500fpm.
    2. if it's too slow and low, your initial RPM setting needs to be increased the next time around; try 100RPM higher, maintain that RPM, and still start with 500fpm.

The key is to bring your approach profile to the point where you only have to make pitch change to an established steady power setting until just prior to the flare.  During the final approach phase, you should be able to add frequent vertical scanning of obstacle (if it exists), aiming point, and the end of runway, on top of an already established scan during downwind and base leg.

Votes

Ronald Levy: 
 

I'm guessing your field doesn't have any sort of visual glide path indicator, or “VGSI”, which could be VASI, PAPI, PLASI, even AOE (alignment of elements). See the AIM for examples of those with which you aren't familiar.  My suggestion is to find an airport where there is such a device and do a lot of practice approaches using the VGSI and focusing on the visual picture.  Try some approaches where you hold yourself high on the VGSI, and then settle down to the VGSI centered position.  Get a feel for the difference in picture of the runway in those various positions.  Then go back to your home 'drome and work on the picture there with reference to what you saw at the VGSI runway.

 

 

 

 

Thank you for this, that is actually one question I had. My home airport has VASI and PAPI on the ends of one runway but not the other. The other airports we've flown to mostly do not (save for one which actually has full precision markings on one runway). I've been debating if I should ask my instructor to try some low approaches without intent to land just to practice getting on the right glide angle on those runways even if the winds dictate use of a different runway

Votes

Andrew Meranda: 
 

What final approach speed are you using? Difficulty in flairing and floating are indications that it's too fast. When you are too high, you often end up diving and picking up too much speed when you get close enough to accurately estimate your glide path and touchdown point. I watch my touchdown point on final to see if it goes up or down in relation to the top of the glare shield. If it moves up, I add power to decrease descent rate. If it goes down, I reduce power to increase descent rate. I maintain final approach airspeed with pitch control. Power (throttle) and pitch (elevator) interact with one another so changing one requires changing the other although there is usually a lag between inputs. Another possibility is that you are turning from downwind to base too soon. I have a 45 degree visual point about halfway between the trailing edge of the wing and the fuselage that I use to decide when to turn base. A strong tail wind on downwind will require me to turn sooner from downwind to base and maintain more power on final but the movement of the touchdown point in the windshield is still my guide for final approach power.

Oh it's definitely an airspeed issue exactly as you described. I think I'm holding too high of a glide path  out of fear of coming up short or too low above the roads and other things and then having to kind of diving it in. I'm trying to get myself over that fear and learn what it should look like so I don't feel like I'm too low when in reality I'm probably not. Hoping to get more days with friendly winds for landing on the PAPI equipped approach because I'm hoping that will help me get a better feel for what the angle should look like.

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1407 Posts

Alyssa Miller: 
 

I've been debating if I should ask my instructor to try some low approaches without intent to land just to practice getting on the right glide angle on those runways even if the winds dictate use of a different runway

The problem with doing that at a nontowered airport is it can get you crossways with other aircraft using the wind-favored runway.  I suggest doing that at either a quiet airport with no other traffic, or one with an operating tower to keep things sorted.