High Density Altitude take offs

[Oldmanb777]

You would need to do that with a 9000 ft D.A.

 

[FastEddieB]

You would need to do that with a 9000 ft D.A.

Its not a perfect solution, but when instructing I would sometimes limit the power on takeoff to less than full to at least simulate the reduction in available power a pilot would face at high DA airports.

 

[John Collins]

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.

The only aircraft that are required to have takeoff and landing distance according to the regulations are:

§23.2620 Airplane flight manual.
The applicant must provide an Airplane Flight Manual that must be delivered with each airplane.

(a) The Airplane Flight Manual must contain the following information—

(1) Airplane operating limitations;

(2) Airplane operating procedures;

(3) Performance information;

(4) Loading information; and

(5) Other information that is necessary for safe operation because of design, operating, or handling characteristics.

(b) The following sections of the Airplane Flight Manual must be approved by the FAA in a manner specified by the administrator—

(1) For low-speed, level 1 and 2 airplanes, those portions of the Airplane Flight Manual containing the information specified in paragraph (a)(1) of this section; and

(2) For high-speed level 1 and 2 airplanes and all level 3 and 4 airplanes, those portions of the Airplane Flight Manual containing the information specified in paragraphs (a)(1) thru (a)(4) of this section.

The definitions of the levels and speeds are contained in:

§23.2005 Certification of normal category airplanes.
(a) Certification in the normal category applies to airplanes with a passenger-seating configuration of 19 or less and a maximum certificated takeoff weight of 19,000 pounds or less.

(b) Airplane certification levels are:

(1) Level 1—for airplanes with a maximum seating configuration of 0 to 1 passengers.

(2) Level 2—for airplanes with a maximum seating configuration of 2 to 6 passengers.

(3) Level 3—for airplanes with a maximum seating configuration of 7 to 9 passengers.

(4) Level 4—for airplanes with a maximum seating configuration of 10 to 19 passengers.

(c) Airplane performance levels are:

(1) Low speed—for airplanes with a VNO and VMO ≤ 250 Knots Calibrated Airspeed (KCAS) and a MMO ≤ 0.6.

(2) High speed—for airplanes with a VNO or VMO > 250 KCAS or a MMO > 0.6.

Most light piston aircraft are going to be Level 1 or 2 and Low Speed and their AFMS are not required to have performance information, just the limitations section.

 

[Huckster79]

I may use my flaps to pop a take off for something stupidly rough… but I think the advice of use ground effect is spot on.

I fly a 1947 Cessna 140, I’ve taken her from Mi to Johnson Creek Idaho twice. I did every take off much like a soft field - not the ground roll portion but the minute she lifted off I was leveling out and flying feet off the ground, sometimes most of the runway, and only once she had really picked up speed would I climb. she handled it well for a 73 yr old 85 hp airplane. Above 9000’ DA I was uncomfortable, but I recall specifically one 8600’ DA take off I felt very comfortable. But my buddies were pleasantly surprised how well she did whom where flying airplanes 95 hp+ greater than her- and I’m confident it was my use of GE that did it.

 

[Tango]

Lots of good info …….drag ! Flaps ! Good point

 

[Palmpilot]

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.

I guess this is a "zoom climb":

https://www.thedrive.com/the-war-zo...departure-from-portland-international-airport