Theoretical question
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Theoretical question
I've asked this question on another forum just thought I would get all your opinions as well.
If you are having the worst day of your life: You are in a microburst and your engine fails, will you be able to accomplish a successful autorotation?
Will you descend quick enough to get the airflow reversed through the rotor system and maintain RPM?
Cooper
If you are having the worst day of your life: You are in a microburst and your engine fails, will you be able to accomplish a successful autorotation?
Will you descend quick enough to get the airflow reversed through the rotor system and maintain RPM?
Cooper
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What a bizarre scenario!
The helicopter doesn't know it is in a microburst, and therefore this will not affect your ability to attain auto and maintain RRPM. Hence, the answer to your question is:
YES - if you react correctly.
The above does not address the situation of transiting through the windhear area: ie experiencing an engine failure moments before passing from stable air into the microburst area. That would be intresting.
When in the microburst, it will not affect your ability to attain auto and maintain RRPM, but the ground might! Since the majority of microbursts occur close to the ground, you may not have time to react, and even if you did, and the microburst you are experiencing is tavelling downwards, you rate of descent relative to the ground will be huge, and as you enter your flare, you will probably be experiencing a significant tailwind as well.
High groundspeed, high rate of descent: no thanks (you really would need the "super-spine"!!
)
The helicopter doesn't know it is in a microburst, and therefore this will not affect your ability to attain auto and maintain RRPM. Hence, the answer to your question is:
YES - if you react correctly.
The above does not address the situation of transiting through the windhear area: ie experiencing an engine failure moments before passing from stable air into the microburst area. That would be intresting.
When in the microburst, it will not affect your ability to attain auto and maintain RRPM, but the ground might! Since the majority of microbursts occur close to the ground, you may not have time to react, and even if you did, and the microburst you are experiencing is tavelling downwards, you rate of descent relative to the ground will be huge, and as you enter your flare, you will probably be experiencing a significant tailwind as well.
High groundspeed, high rate of descent: no thanks (you really would need the "super-spine"!!
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Actually you got the sceanario I was going for right on. You have an engine failure just as you are entering the microburst so the helicopter is not descending with the parcel of air yet.
Also, I think I have a pretty good idea of the stagnation point in blade icing but I still cant understand how water can make its way through the high pressure in front of the leading edge. Any takers?
Also, I think I have a pretty good idea of the stagnation point in blade icing but I still cant understand how water can make its way through the high pressure in front of the leading edge. Any takers?
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Having been caught in a microburst once and escaped very close to the treetops despite full engine power and min power speed, I think it is quite possible that an aircraft might not survive such a double whammy.
Regarding the water penetrating the high pressure area in the front of a blade: Can you imagine a stone from a catapult not being able to fly through the air because the wind is strong? It might get deflected, but it still goes throught the air. Inertia, my dear chap.
Regarding the water penetrating the high pressure area in the front of a blade: Can you imagine a stone from a catapult not being able to fly through the air because the wind is strong? It might get deflected, but it still goes throught the air. Inertia, my dear chap.
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Inertia, my dear chap......that'll be the same as momentum then!!
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