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ACS V speeds workaround

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ACS V speeds workaround

It is encouraging that the ACS calls for acceleration in ground effect to Vx or Vy as appropriate on the soft field takeoff. Here is recognition that there is actually greater acceleration potential in ground effect. Why that free ground effect energy is not also recommend for normal and especially short field takeoff is beyond comprehension. Nothing soured me more on the old PTS than being test situation forced to roll on the ground down so much runway that could be accelerated over so much more efficiently in low ground effect. And even worse was pitching up to a Vx pitch attitude long, long, long, long, before necessary. This resulted in hanging on the prop in a max gross or often over gross C-150s where engine failure would almost certainly result in stall...in the Midwest. In Flagstaff it would result in the airplane mushing back onto the runway. At least the poor student, and instructor, couldn't get high enough to hurt themselves.

So what did we do? Of course we worked around this dangerous techniques.

Vy on normal takeoff (+10 knots allowed) perhaps survivable.
Vx or Vy as appropriate on soft field (+10 knots allowed). This was always the best soft field (and the best actual non-test short field and normal takeoff) as long as we used dynamic proactive elevator to nail level in low ground effect.
Vx on short field +10 knots.
Hopefully DMMS, Defined Minimum Maneuvering Speed, will become normal after hanging on the prop initially.
All stabilized approach airspeed can be 1.3 Vso-5 knots. Deceleration on short final, absolutely necessary on true short field, isn't going to happen. The best instructors can do is cheat some power remaining in an early round out and hold off.

I strongly question how the short field approach can touch down within 200' PA.IV.F.S10, using the exact same 1.3 Vso approach airspeed as the normal approach which can touch down within 400' PA.IV.B.S10.

Does the throttle have to be closed, rejecting it as the effective descent stabilization control, to pass the flight test?

Will the fact that upset, loss of control, and controlled flight into terrain is killing as many pilots as ever trigger more than just adding some good terminology like ground effect and energy management to the flight test? I don't know. But until safe maneuvering flight techniques are actually taught students, until low altitude orientation is accepted along with high altitude orientation, LOC, upset, and CFIT will continue to kill as many pilots each year.
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Re: ACS V speeds workaround

You need some medication Contact :mrgreen: I don't know how you can complicate something like flying so much. Maybe it's my limited intelligence, I have trouble grasping your concepts.
I just take off, bit longer with a load.
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Re: ACS V speeds workaround

Do you default pitch to Vx as soon as you are accelerated to Vx just because there is an obstruction way, way down at the end of the runway? With a full hopper?

Do you normally climb at Vy? With a full hopper?

Do you normally make a climbing turn to crosswind, starting at Vy? Does a climbing turn at Vy at 400'AGL seem safe? Can you recover from an inadvertent stall at 400' AGL?

Do you normally cross the numbers faster than Vso? Do airplanes even land well at Vso. Are they actually stalled at Vso in low ground effect?

Why do the numbers appear to speed up on short final at 1.3 Vso? Why doesn't the stop sign at an intersection on the highway appear to speed up?

More importantly, can we instructors do anything to alleviate maneuvering flight fatalities around the airport?

When sitting on the picnic table at the airport, why do I hear wind whistling as most airplanes overfly the numbers?

Why do takeoff stalls result In many more fatalities than the far more landing incidents and accidents?
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Re: ACS V speeds workaround

Is it fair to suggest that the 172, Diamond DA-40 and taper wing Archer/Warrior which represent the bulk of basic training hours have negligible accident rates related to loss of control during take off, circuits and landing?

In part this has been design led, with the taper wing Piper and Diamond perhaps not ever recording a stall spin fatality for the type. In part the use of stabilised approach technique which, perhaps not ideal, as an old timer might correctly suggest being able to glide to a threshold is good airmanship.

The main accident incidents appear to be runway excursion due to poor crosswind technique.

I recognise the PPL course is not an ideal training regime for back country operations, but don’t believe the LOC statistics in the training VFR/PPL environment are the chronic condition that they once were.
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Re: ACS V speeds workaround

I don't know how to calibrate individual data, but summary indicates while incidents and accidents have declined f fatalities per accident have remained the same.

It is interesting how many survivors of takeoff accidents thought the problem was power loss or diminished power.

Oldfart, why can't the just over the obstruction with zoom reserve technique from spraying apply to the overgross C-150 trainer? The physics and danger are identical. How many instructional flights use ground effect and clear just over and what percentage of fatalities are dual? Scary.
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Re: ACS V speeds workaround

Contact, I have no idea what vx, vy and vz is. Don't look at ASI, go by feel/ aircraft attitude and other cues.

For pilots just starting out they need to be able to reference speeds as they learn, buy there's no way they need to complicate things too much. A student pilot is not going to be flying a heavily loaded aircraft dragging over trees.

I feel by making flying seem so complicated is that it discourages prospective pilots away from learning to fly.
Flying an aircraft is a joy, a 3 dimensional adventure with a constantly evolving view of our natural world..

If you have to have a degree in aeronautics and a Masters in aeronautical V reference speeds then that is going to put people off what is really a basic skill that can be learned in a few hours. There is a lifetime of learning that follows if you pursue flying as a calling or vocation.
Flying an aircraft is a skill most people can learn, you don't have to be a university graduate to fly an aircraft.
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Re: ACS V speeds workaround

That I agree with very much. I will just add that the techniques I have mentioned are easy to learn and require no instrument. My students soloed in six hours without ever using the airspeed indicator.
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Re: ACS V speeds workaround

The really unfortunate thing is that the basic skill that you point out can be learned in a few hours without instruments is not learned until after the license. Because of the law of primacy, those confusing V speeds are internalized and given way too much default. Some drive around for years never learning to fly. We have long runways and reliable auto pilots and a good ATC system. But there is still that tenacious fatalities statistic. They really want to do better and I have always know FAA examiners, when they did the test, and DPEs since, who have enough common sense to let a student who can obviously fly do so...even at more than 20 degrees of bank. I have know examiners who were crop dusters who had no problem with a student allowing the nose to go down naturally in turns in the pattern...all turns in the pattern. No, they certainty are not the norm.
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