Power chop and turbine loss? What to do.

[DmitriKozlowsky]

I wanted to practice worst case autorotations. Didn't quite work.

First I chopped power. Open the cover then depressed button for 1 second. Nothing happened. Aircraft kept flying, and there was no power loss. What does power chop suppoused to do?

Then I tried loss of power. Throttle to idle then throttle OFF. Total loss of power, total loss of generator. Lost all control! No cyclic, no pedals, no collective. No control at all,so no autorot possible. I guess loosing powerplants in Apache is death. Wouldn't the spinning rotor keep emergency generator and hydralics running to allow autorot?

[bradmick]

The chop button electronically reduces the engines to idle. That being said, not sure if it’s implemented yet.

 

if you allow the main rotor speed to go low enough, the generators will kick offline, and eventually due to a lack of lift and energy in the rotor all control will be lost. The dcs Apache hasn’t been able to auto since day 1 due to excessive drag on the rotor. The other thing to keep in mind is that the rotor is an extremely low inertia rotor, it will bleed energy extremely fast. If you’re really into practicing this maneuver, then get the collective fully down and then bring the power levers to idle. It’s the only more or less safe way to practice a power off auto (which we don’t do in the real helicopter by the way).

Edited November 5, 2023 by bradmick

[DmitriKozlowsky]

19 hours ago, bradmick said:

The chop button electronically reduces the engines to idle. That being said, not sure if it’s implemented yet.

 

if you allow the main rotor speed to go low enough, the generators will kick offline, and eventually due to a lack of lift and energy in the rotor all control will be lost. The dcs Apache hasn’t been able to auto since day 1 due to excessive drag on the rotor. The other thing to keep in mind is that the rotor is an extremely low inertia rotor, it will bleed energy extremely fast. If you’re really into practicing this maneuver, then get the collective fully down and then bring the power levers to idle. It’s the only more or less safe way to practice a power off auto (which we don’t do in the real helicopter by the way).

 

How can Army approve combat helicopter for operational service if aircraft cannot autorotate?

[admiki]

It can autorotate, just the risk is too high to do full down auto as a practice. As long as you can enter autorotation and keep RPM, you should survive the landing. Not to mention it's low probability to lose both engines and you also have sim for stuff like that.

[bradmick]

When I said the aircraft can’t autorotate, I specified the DCS one. The real helicopter autos just fine. DCS does not.

[Dragon1-1]

On 11/6/2023 at 9:50 AM, admiki said:

It can autorotate, just the risk is too high to do full down auto as a practice. 

That's what flight sims are for.  I sure hope this gets corrected so we can practice these emergency procedures.

[DmitriKozlowsky]

Well I am  not sure it even matters in practice. Every time I am hit with MANPADS, 23mm, 40mm, or higher, the pilot is killed or blacks out , or tail separates. The damage model, I suspect , is a lot weaker then real one. Survivability is low. At close range , .50BMG or Russian/Chinese equivalent shoots down where tail separates or tail rotor is destroyed.

[bradmick]

Well, there isn’t an aircraft designed that’ll take that sort of damage and shrug it off. You’re talking about high caliber systems. The goal is to avoid getting shot, because you’re likely not going to survive the encounter….which makes practicing autorotations moot.