High Density Altitude take offs

Fwiw
I'm planning a trip to yellowstone next summer, and looking to land at cody, wy, elev. 5102. According to the charts in my poh, no flaps should take 4800' to clear 50', while 25 deg. flaps should take 3400. This is max gross on a warm day with no wind.

rhkennerly said:
Even in planes that have solid DA charts in the poh, there is still value in the old Koch Chart. For older planes with no good DA info, Koch is indispensable. Personally, I do a lot more sober reflecting when I have to stop to calculate “TO run increases 300% & Rate of Climb is reduced by 70%,” than when I use a look up table.

a side benefit Of Koch is that you also get a feeling for how squishy the hard numbers found in some poh really are. “Maybe I should plan for 400% increase in TO run & 80% decrease in ROC, just in case.”
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That's cool. First time I've seen it.
 
My C170 manual mentioned flaps can hinder TO perf with high DA. I’ll get a pic of the actual wording.

Airspeed is your friend and that DA is robbing AS by reduced engine power. Also, drag from any flap usage is hindering your AS.

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Oldmanb777 said:
Lift over drag maybe the same, but you are not power limited in a sailplane, you already have the energy you need to fly. You are not trying to leave a runway with enough performance to climb away from the ground.
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Agreed that the power is reduced by the DA, though I also think you want best L/D for that climb and whatever configuration produces it.
 
Leaning to max RPM gets the most out of the engine. There is a greater degree of extra free energy, however, out of low ground effect. We accelerate better without the pitch attitude of the tail on the ground so level it as soon as possible (TW AC.) We accelerate better with the nose wheel just off or lightly rolling on the surface so get the nose wheel light or just off as soon as possible. The wing will lift the weight of the aircraft in low ground effect at a much slower airspeed than Vso so get the mains just off into low ground effect as soon as possible. We accelerate better level in low ground effect so once off push the nose over to level (a little dynamic proactive elevator may help us get level without touching back down) as soon as the mains are off. With no obstacle we gain the most free ground effect energy by staying level in low ground effect until cruise on long runways. In most high mountain shorter runways we usually can continue off the departure end in low ground effect, especially if we have departed down drainage. With obstacle, it is still most efficient to remain in low ground effect until near the obstacle and then zoom over the obstacle with the outcome far less in doubt than up out of ground effect at Vx or Vy as appropriate. A problem with that wordage is that Vx or Vy is only appropriate when it works out that we are near the obstacle at Vx or Vy. With no obstacle, neither Vx nor Vy is ever appropriate. Low ground effect for the absolute best acceleration is alway appropriate; as much as we can get before cruise or having to climb. Down drainage (free potential energy of altitude) there is no absolute need to climb until the Gulf of Mexico or the Gulf of California or the Pacific ocean. The idea that we must climb out of ground effect is a high density altitude killer.

Once off down drainage with low powered airplanes, the next source of free energy is thermal lift or orographic lift. There is no guarantee of engine climb. The free part of thermal is that we can fly slow in up air and fast through down air for net gain in both altitude and ground speed. The free part of orographic energy is that riding the downwind ridge of a ridge valley ridge system up toward the pass gives us the best of both horizontal space available and vertical space available and the slowest ground speed and shortest diameter of turn should we need to turn back down drainage. We do have to bail and make the turn back allowing the nose to go down naturally (no load factor at any bank angle) before the valley tightens us out of both horizontal and vertical space available.

Brcase, Brian I think, the glider pilot, understands this stuff. Low powered airplanes are just powered gliders at high Da, but do really well using all that free energy.
 
Cody can be a great place to visit. We lived there for a time while I was furloughed. I don't remember any 50 ft obstacle, however there is rising terrain in most all quadrants. The exception is toward Powel. So having good climb performance is best. You have a long runway, so in most cases you will not be runway limited, but probably climb limited. There is a minium climb gradient to maintain. Can you maintain that with flaps down? Even in a minimum settign such as 10 degrees? Or would you be better off using the excess runway to accelerate to a clean configuration for better climb performance?
 
Jimmy Allen Dulin said:
We accelerate better with the nose wheel just off or lightly rolling on the surface so get the nose wheel light or just off as soon as possible. The wing will lift the weight of the aircraft in low ground effect at a much slower airspeed than Vso so get the mains just off into low ground effect as soon as possible.
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I don’t want to belabor the point, but…

1) I’d love to see some experiments, first doing what you describe, and then doing what the Airplane Flying Handbook describes for a short field takeoff as quoted upthread. Then see which results in more altitude at a given point after takeoff. I remain open to the possibility that your way may result in more altitude gained, but I remain skeptical.

2) A note to student pilots: On your checkride, it would be best to adhere to recommendations in the Airplane Flying Handbook. What Jimmy suggests above is more indicative of a soft field takeoff, and I could see an examiner docking an applicant for performing in that manner if asked to do a short field takeoff. The Private Pilot ACS agrees, mentioning raising the nose and taking weight off the mains for a soft field, but not a short field takeoff. Once your ticket is in hand, of course feel free to experiment, as suggested above.
 
You also use less distance on short field when you don't come to a complete stop. Inertia and all that jazz. So the AFH isn't the end all be all of facts.
 
FastEddieB said:
I don’t want to belabor the point, but…

1) I’d love to see some experiments, first doing what you describe, and then doing what the Airplane Flying Handbook describes for a short field takeoff as quoted upthread. Then see which results in more altitude at a given point after takeoff. I remain open to the possibility that your way may result in more altitude gained, but I remain skeptical.
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Funny. I notice @Jimmy Allen Dulin posts his location as "Kolorado." Assuming he does mean the state, I'd guess the two two guys who recommend this technique at very high density altitude have done it in such places as Leadville where the D-Alt typically reaches into the teens.

Just to be clear, I don't use this technique at low density altitudes like 7,000 or 8,000. It's just not necessary. I only mentioned it because the OP was talking about density altitudes over 9,000. Even then, it was to explain why many use flaps for takeoff (which Sparky Imeson recommends in his Mountain Flying Bible) and it absolutely depends on what you are flying. At 10,000 D-Alt, an LSA with two people on board (who just had a pancake breakfast) has a little less available net power than a Turbo Arrow producing 41" MP and a different technique might be appropriate.
 
PeterNSteinmetz said:
Is there actually any regulation prohibiting extrapolating responsibly, like using a Koch chart, beyond the boundaries of the performance tables?
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Since it’s not published as a limitation, 91.103(b) is the reference for performance requirements in our light airplanes…note the ability to use “other reliable information” if an AFM was not required for certification of the airplane.
(b) For any flight, runway lengths at airports of intended use, and the following takeoff and landing distance information:

(1) For civil aircraft for which an approved Airplane or Rotorcraft Flight Manual containing takeoff and landing distance data is required, the takeoff and landing distance data contained therein; and

(2) For civil aircraft other than those specified in paragraph (b)(1) of this section, other reliable information appropriate to the aircraft, relating to aircraft performance under expected values of airport elevation and runway slope, aircraft gross weight, and wind and temperature.
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MauleSkinner said:
Since it’s not published as a limitation, 91.103(b) is the reference for performance requirements in our light airplanes…note the ability to use “other reliable information” if an AFM was not required for certification of the airplane.
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And note that 91.103 only requires the pilot to "become familiar" with the information, which does not seem to require it to be treated as a legal limitation (although it could turn out to be a practical limitation).

§91.103 Preflight action.

Each pilot in command shall, before beginning a flight, become familiar with all available information concerning that flight. This information must include—

(a) For a flight under IFR or a flight not in the vicinity of an airport, weather reports and forecasts, fuel requirements, alternatives available if the planned flight cannot be completed, and any known traffic delays of which the pilot in command has been advised by ATC;

(b) For any flight, runway lengths at airports of intended use, and the following takeoff and landing distance information:

(1) For civil aircraft for which an approved Airplane or Rotorcraft Flight Manual containing takeoff and landing distance data is required, the takeoff and landing distance data contained therein; and

(2) For civil aircraft other than those specified in paragraph (b)(1) of this section, other reliable information appropriate to the aircraft, relating to aircraft performance under expected values of airport elevation and runway slope, aircraft gross weight, and wind and temperature.
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Palmpilot said:
And note that 91.103 only requires the pilot to "become familiar" with the information, which does not seem to require it to be treated as a legal limitation (although it could turn out to be a practical limitation).
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In order to become familiar with something, it has to exist in some form.

or are you saying, “Mr. FAA Man, I noted that the information I have shows that I don’t have the performance capability to take off at this density altitude, but there’s no legal requirement to have that capability, so I tried it anyway,”? ;)
 
MauleSkinner said:
In order to become familiar with something, it has to exist in some form.

or are you saying, “Mr. FAA Man, I noted that the information I have shows that I don’t have the performance capability to take off at this density altitude, but there’s no legal requirement to have that capability, so I tried it anyway,”? ;)
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I'm saying that if the aircraft is required to have "an approved Airplane or Rotorcraft Flight Manual containing takeoff and landing distance data," I hope that the FAA will not use it as an excuse to claim extrapolation is not allowed.
 
Palmpilot said:
I'm saying that if the aircraft is required to have "an approved Airplane or Rotorcraft Flight Manual containing takeoff and landing distance data," I hope that the FAA will not use it as an excuse to claim extrapolation is not allowed.
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Having never flown a light aircraft that required one, I wouldn’t know.

Edit…I think King Airs fall under the AFM requirement, but I can’t remember if the limitations section reflects a requirement to comply with takeoff charts or not.
 
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MauleSkinner said:
In order to become familiar with something, it has to exist in some form.

or are you saying, “Mr. FAA Man, I noted that the information I have shows that I don’t have the performance capability to take off at this density altitude, but there’s no legal requirement to have that capability, so I tried it anyway,”? ;)
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That's pretty much SOP in high density ops when you are off the published chart. My first high D-Alt mountain flight was while on vacation. 172 out of Leadville. It exists in the collective experience of mountain instructors.
 
Leadville is an excellent place to do mountain training. It was one of my "go to places" for mountain training when I was instructing.
 
One thing to consider is that the rolling friction from your wheels will be greater at higher altitude.

If the rotation speed is 60kts indicated, then at 9000ft DA, that will translate to 70kts true. Friction being proportional to the square of the velocity, you'd expect 36% more rolling friction at 70kts true than at 60kts true.

My suspicion is that rolling friction from the wheels is a pretty small contributor to the overall drag on takeoff on a paved runway, but I don't know for sure.
 
FastEddieB, at least the ACS (2003 revision I think) now calls for acceleration in ground effect to Vx or Vy as appropriate. Neither is appropriate if that means climbing out of low ground effect early and forfeiting free ground effect acceleration energy forever. As an instructor, I have never accepted hanging on the prop at Vx at 50' AGL hundreds of feet before the obstruction. Now, as Wolfgang points out, the student may have to point the nose at the obstruction halfway up to gain enough airspeed (kinetic energy) to zoom over the obstruction. There is no guarantee, hanging out of ground effect too soon to go over, that natural elements will remain stable enough for that technique to work.

If it is now accepted by authorities that ground effect energy is valuable on takeoff, why are they still willing to forfeit most of it?
 
CaptainXap said:
Friction being proportional to the square of the velocity…
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That didn’t sound right, so I googled it. Rolling resistance increases linearly, not geometrically. And it sure seems to start out at a very low level, given the fact that most GA planes can be moved by a single person on level ground.

Getting the weight off the wheels is critical on a soft field. But on pavement, my guess is the increased induced and form drag created by raising the nose early far outweighs the gains assumed by getting the gear in the air.

But I’m not an engineer nor a physicist. Easier than getting into the math and physics maybe just experiment with both techniques and see which is more effective over an obstacle. I’d be happy to help out if anyone wants to make a go of it.
 
CaptainXap, rolling friction from the wheels is the greatest contributor to the overall drag on takeoff on a paved runway. Some confusion/error on ground effect is the difference in pitch attitude. Slugging along (little acceleration) at high pitch attitude is not helpful. Low powered airplane do not accelerate well at high pitch attitude and high powered airplanes attempt to fly out of low ground effect too quickly. As soon as we come off the surface at an airspeed that will lift the weight of the airplane in low ground effect, we need to pitch down to level the fuselage in low ground effect. The easiest and most comfortable way is dynamic proactive elevator movement. We pitch down more than comfortable (it is really hard to catch the prop) and immediately pitch up more than necessary, down up down up etc to bracket level fuselage. My experience with students is that without briefing on and use of this technique they will not pitch down to level the fuselage successfully. They will stay at high pitch attitude and accelerate poorly in low powered airplanes or fly out of low ground effect in high powered airplanes. Try getting off as soon as possible as in the old soft field and then try dynamic proactive elevator movement.

The old soft field technique, if the fuselage was leveled, actually got the airplane of shorter than the short field pitch up at Vx technique did. Acceleration in low ground effect, makes the greatest energy difference. Where else do we get so much free energy? Ground effect boats cruise much, much faster that those that slog along on the surface.
 
But at a high DA, the air pressure in the tires should be higher if they aren't leaking, thereby reducing the friction on the pavement.

Hold on, the nit harvest is ready. Gotta go get picking.
 
CaptainXap, yes try it. You will like it. Notice that the Ag planes, even the newer turboprop million dollar rigs go out every time in low ground effect. Notice that the spray fields in soggy country only pave the first quarter of their strips. Over the mud they are in low ground effect. At the end of the pavement there is now way they can carry a full hopper out of ground effect.
 
Jimmy Allen Dulin said:
Acceleration in low ground effect, makes the greatest energy difference. Where else do we get so much free energy? Ground effect boats cruise much, much faster that those that slog along on the surface.
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I’m all for taking advantage of ground effect. True, induced drag is reduced in ground effect. But what drag there is, is increasing geometrically with the increase in speed. That’s why keeping the plane in ground effect well beyond Vx to “zoom climb” over an obstacle may or may not be as effective in clearing an obstacle as just nailing Vx and holding it through the climb. May depend on a lot of factors.
 
midlifeflyer said:
Mine too, when I was instructing in Colorado. Glenwood Springs was another regular.
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I often did a round robin of the Leadville, Glenwood, Granby for check outs, and training. Kremling was another good one. If the pilot had lots of experience I would throw in Marble and even did a few King Ranch as well as a private strip on Grand Mesa. Some great flying for sure. I would like to do some of that again before I'm too old.
 
If tried, the extra free energy of level in low ground effect is so noticeable that you will never hang your life on Vx except in true only able to get to Vx in low ground effect just before the obstruction (true short field.) The average response time to accept that the engine has failed and to start lowering the nose is three seconds. What is the math on three seconds at Vx pitch attitude with no engine or ground effect thrust? I have lost the engine five times in low ground effect. Landed on remaining runway once and zoomed up engine dead four time to find suitable landing site in near horizon. I worked low for 17,000 hours. I wanted to have some money in my pocket down there. I didn't want to have to bank on money in the bank, which I didn't have anyway. Until about a thousand feet, and immediate push the nose down there, recovery from stall is improbable. That 100' altitude (bank) with no money (airspeed) in my pocket just doesn't appeal to me. There are a lot more natural factors at 100' than in ground effect. Downdraft, in low ground effect does not happen. In a dust devil we are moved sideways, not slammed into the earth. Wind doesn't work that way. Shear or downdraft off terrain or buildings can put an airplane down at 100', but that doesn't happen often. Usually the pilot pulls back insisting on the 100' and stalls and falls 100' to the ground. In 100', the nose has plenty of vertical space available to pitch well down. Recovery requires pitching down, the pitch up to prevent this is just going to accelerate the fall.

Wolfgang said airspeed is altitude and altitude is airspeed and the math should be that they are equal. Human nature prevents it from happening that way. The safe way to use less than a thousand feet of potential energy of altitude is to take off down drainage in low ground effect to get the best of both forms of energy. The outcome of the maneuver will never be in doubt. i just couldn't teach the Vx technique. The outcome of the maneuver was always, always in doubt. That was true even when the student nailed it. I begged students to take the +5 knots variance given by the very, very unsafe PTS later becoming ACS. That Vx crap is statistically fatal.

And like someone here said, Vx does not exist at high DA. It becomes Vy. And if the outcome of Vy is also in doubt, due to DA, takeoff down drainage in low ground effect and stay in low ground effect out over the desert if practicable. The outcome of the maneuver is not as likely to be in doubt in the heat of the day and wind when pipeline guys have to fly anyway.
 
Oldmanb777 said:
I often did a round robin of the Leadville, Glenwood, Granby for check outs, and training. Kremling was another good one. If the pilot had lots of experience I would throw in Marble and even did a few King Ranch as well as a private strip on Grand Mesa. Some great flying for sure. I would like to do some of that again before I'm too old.
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The Granby (or Kremmling depending on weather) - Glenwood - sometimes Aspen - Leadville run was a staple for most because they taught different things. Personally, I liked to sometimes add Buena Vista when the winds were southerly, because taking off at Leadville and then descending for a straight in at Buena Vista, sometimes without ever going to pattern altitude at Leadville, was just interesting.

Sadly, having flow club and rental aircraft, I mostly stuck with the public paved mountain airports and never visited Marble.
 
I taught in Fred Shotenboeur's C-140 and Grummins at Monte Vista and in Ken Leach's newer Cessnas at Center in the San Louis Valley of Colorado summers while my wife attended Adams State College. Climbing to a thousand feet pattern altitude was not what my students had to pay for. They learned to fly quite well at lower AGL. For mountain work, we found some up air somewhere.
 
Oldmanb777 said:
And you leave the runway with less energy and need to overcome that on climb, when slow and generating the most drag.
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if you leave the runway at the proper airspeed, your energy level is the same, low or high density altitude. That does assume you have chosen a runway that doesn’t require short field technique.
 
Based on new ACS instructions, "accelerate in ground effect to Vx or Vy as appropriate," there is not V speed given for leaving the runway. That would be at whatever in ground effect airspeed would provide the lift. If you are going by the old PTS proper airspeed for leaving the runway, that would be Vx or Vy as appropriate. We have already determined that Vx does not exist at high density altitude but rather becomes Vy. The change in instructions was because the authorities had to finally admit they were doing all takeoffs, save soft field, in a less efficient way, "pitch to Vx or Vy as appropriate." My hope and mission, bothering so many compliant aviators, is that the authorities will finally, someday, see that from low ground effect pitching to Vx or Vy leaves a lot of free energy unused if that pitch to Vx or Vy (from ground effect flight) happens before all possible acceleration in ground effect happens with no necessity of climbing over an obstruction or just early if there is an obstruction.

We have lost a lot of free (no fossil fuel necessary) energy, and a lot of airplanes, rolling on the ground to Vx or Vy as appropriate. We now are losing a lot of free energy, and fewer bur a significant number of airplanes, pitching to Vx or Vy as appropriate when continuing in low ground effect would produce enough energy to make it, especially if we were headed down drainage.
 
Jimmy Allen Dulin said:
If tried, the extra free energy of level in low ground effect is so noticeable that you will never hang your life on Vx except in true only able to get to Vx in low ground effect just before the obstruction (true short field.) The average response time to accept that the engine has failed and to start lowering the nose is three seconds. What is the math on three seconds at Vx pitch attitude with no engine or ground effect thrust? I have lost the engine five times in low ground effect. Landed on remaining runway once and zoomed up engine dead four time to find suitable landing site in near horizon. I worked low for 17,000 hours. I wanted to have some money in my pocket down there. I didn't want to have to bank on money in the bank, which I didn't have anyway. Until about a thousand feet, and immediate push the nose down there, recovery from stall is improbable. That 100' altitude (bank) with no money (airspeed) in my pocket just doesn't appeal to me. There are a lot more natural factors at 100' than in ground effect. Downdraft, in low ground effect does not happen. In a dust devil we are moved sideways, not slammed into the earth. Wind doesn't work that way. Shear or downdraft off terrain or buildings can put an airplane down at 100', but that doesn't happen often. Usually the pilot pulls back insisting on the 100' and stalls and falls 100' to the ground. In 100', the nose has plenty of vertical space available to pitch well down. Recovery requires pitching down, the pitch up to prevent this is just going to accelerate the fall.

Wolfgang said airspeed is altitude and altitude is airspeed and the math should be that they are equal. Human nature prevents it from happening that way. The safe way to use less than a thousand feet of potential energy of altitude is to take off down drainage in low ground effect to get the best of both forms of energy. The outcome of the maneuver will never be in doubt. i just couldn't teach the Vx technique. The outcome of the maneuver was always, always in doubt. That was true even when the student nailed it. I begged students to take the +5 knots variance given by the very, very unsafe PTS later becoming ACS. That Vx crap is statistically fatal.

And like someone here said, Vx does not exist at high DA. It becomes Vy. And if the outcome of Vy is also in doubt, due to DA, takeoff down drainage in low ground effect and stay in low ground effect out over the desert if practicable. The outcome of the maneuver is not as likely to be in doubt in the heat of the day and wind when pipeline guys have to fly anyway.
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Jimmy Allen Dulin said:
Based on new ACS instructions, "accelerate in ground effect to Vx or Vy as appropriate," there is not V speed given for leaving the runway. That would be at whatever in ground effect airspeed would provide the lift. If you are going by the old PTS proper airspeed for leaving the runway, that would be Vx or Vy as appropriate. We have already determined that Vx does not exist at high density altitude but rather becomes Vy. The change in instructions was because the authorities had to finally admit they were doing all takeoffs, save soft field, in a less efficient way, "pitch to Vx or Vy as appropriate." My hope and mission, bothering so many compliant aviators, is that the authorities will finally, someday, see that from low ground effect pitching to Vx or Vy leaves a lot of free energy unused if that pitch to Vx or Vy (from ground effect flight) happens before all possible acceleration in ground effect happens with no necessity of climbing over an obstruction or just early if there is an obstruction.

We have lost a lot of free (no fossil fuel necessary) energy, and a lot of airplanes, rolling on the ground to Vx or Vy as appropriate. We now are losing a lot of free energy, and fewer bur a significant number of airplanes, pitching to Vx or Vy as appropriate when continuing in low ground effect would produce enough energy to make it, especially if we were headed down drainage.
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Eight years ago, there was quite a controversy about this in the following threads, in which it was referred to as a "zoom climb":

https://www.pilotsofamerica.com/community/threads/12-seconds-to-pattern-altitude.62578/

https://www.pilotsofamerica.com/community/threads/departures-vx-vy-or-zoom.62798/
 
Interesting Palmpilot, but my orientation isn't concerned with time to 1,000' or even going to 1,000.' Because of the way I worked, both crop dusting and pipeline patrolling, I never went there. My orientation, concern, is with maneuvering airspeed at all times when below 1,000,' what Dan Gryder calls DMMS (Determined Minimum Maneuvering Speed.) All pilots are indoctrinated with high altitude orientation, the idea that only altitude is safe. That orientation completely discounts the time we are not high enough to recover from stall, with or without spin. 99% of my 17,000 logged hours were 200' or below. I naturally developed low altitude orientation. Altitude gave me potential energy which I converted into kinetic in only one of my 13 engine failures. That is why the title to one of my free ebooks is "Safe Maneuvering Flight Techniques." Email me jadulin@gmail.com for that and "Contact Flying Revised", also free. Low and slow is nostalgic, but not safe. If in any of the 65 hp airplanes I instructed in (almost all of them) I desired to have most of the sixty miles per hour airspeed possible until short final where I used elevator pitch to slow enough to sink and power sufficient to control that sink (glide angle) and rate of descent to touchdown without the use of the more difficult zero thrust round out and hold off (long hold off in light airplanes that show airspeed pegged on three point touchdown in low ground effect.) Vso has nothing to do with that in any airplane.

Wolfgang's "zoom climb" is the first part of his "law of the roller coaster" and his "airspeed is altitude and altitude is airspeed." We gunnery pilots (Cobra for me) and crop dusters use the law of the roller coaster on every energy management turn, gunship return to target, zoom climb followed by allowing the nose to go down naturally in the turn (all turns) or whatever you want to call it.

At cruise airspeed in low ground effect over the runway or crop field, pull up smoothly into a zoom climb wings level. (With no significant crosswind a P turn back or teardrop turn back is necessary involving two energy management turns but we won't go there just now. We are going to assume enough crosswind, which is how we work in wind, to require only one energy management turn.) So we have zoom climbed up a couple hundred feet at most (airspeed is altitude but zoom decays at high pitch attitude.) Now at much slower airspeed (the slower we go the faster we turn with a much smaller turn radius or diameter) we bank at whatever bank will achieve a return to the target or crop row 35 feet upwind from the crop row we left. We do not hold much back pressure on the elevator in this 1 go at any bank turn. Back pressure in turn equals load factor and more than 1g. No back pressure, or little, we remain near 1g. Much rudder is required in steep turns and we need to get the nose around and onto target before the resultant dive puts us into terrain. We really need to push the nose around. And past 45 degree of bank, the rudder is pushing the nose down as much as horizontally. We are not skidding significantly, it just takes a lot of rudder. And skid is no more dangerous than slip with the nose well down. In steep turns without pulling back on the stick, the nose will go well down. We are now converting potential energy into kinetic, altitude into airspeed. We will go back into the field as fast as we were going in low ground effect in the field. Finally we must level the wing before the pull up to level out at low ground effect again in the field. We don't want to create the graveyard spiral by pulling up with a wing down and we don't want to put a down wing through a wire or into obstructions or terrain.

The hugh teaching point, best learned on crooked pipelines rather than crop dusting, is that all energy management turns need not be steep turns. If the change of heading is minor on a pipeline, we can pitch up just a bit, bank sufficient to put the nose down onto the new target (pipeline right of way in new direction) while allowing the nose to go down onto the right of way in the new direction. Two things befuddle high altitude orientation pilots. We have to anticipate the need to turn, not just bank and yank. And the safety crux, we have to release back pressure in the turn to maintain 1g. This is the safety VFR turn for every pilot, I'm just having a hard time selling it. Along with high altitude orientation, we have been indoctrinated in the integration of contact flying skills and instrument flying skills. The two really do not mesh well. We are not looking out enough VFR and we certainly don't want energy management turns IFR.

The only thing, in my opinion, that will send fatalities down with the improved accident rate is changing from demanding level turns and climbing turns in the pattern. My students have no problem, nor does the world evaporate, if the allow the nose to go down as designed in level turns and then return to level flight. Nor do they have any problem if they allow the nose to go down naturally in climbing turns and return to the climb wings level after the turn.
 
It can be a pretty simple test. Take off with flaps at 20, then come back around and do it with no flaps. In my airplane, with no flaps the take off roll is noticeably longer.
 
Wagondriver said:
It can be a pretty simple test. Take off with flaps at 20, then come back around and do it with no flaps. In my airplane, with no flaps the take off roll is noticeably longer.
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I think a better test is trying it both ways and measuring height above the far runway end or other prominent feature.
 
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