Why do military helicopters crash rather than autorotate?
Ian, I'd say he hit pretty hard. 
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Why they need tail rotors
Hi I am Brandon I am 10 and I have study about planes and helicopters. The reason why they need an tail rotor it to keep it steady during flight if they do not have a tail rotor they would simply keep turning till they crash and possible explode in fire. If you have any comments or questions email me at [email protected] thank you
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The Tail Rotor :
The tail rotor is very important. If you spin a rotor using an engine, the rotor will rotate, but the engine and the helicopter will try to rotate in the opposite direction.
This is called
TORQUE REACTION.
The tail rotor is used like a small propeller, to pull against torque reaction and hold the helicopter straight.
Source: Principles of rotary flight
The tail rotor is very important. If you spin a rotor using an engine, the rotor will rotate, but the engine and the helicopter will try to rotate in the opposite direction.
This is called
TORQUE REACTION.
The tail rotor is used like a small propeller, to pull against torque reaction and hold the helicopter straight.
Source: Principles of rotary flight
Mini....just how does one "dodge" Rounds? I know the Brits do that by quaffing back a half dozen Pints bought by others then looking at their Breitling and muttering something to the effect they "must be off" and "Cheerio!".
Jack, I don't think CH-53E's typically fly with JP-4. JP-5 and JP-8 are the preferred fuels. FWIW. 
(Better BTU per pound, higher flashpoint, etc)
(Better BTU per pound, higher flashpoint, etc)
LW50, I was thinking more in terms what affect 2000 gallons of fuel would have on the potential survivability of a crash. As a reference, the Marines had a CH-53D with 650 gal external aux tanks crash in a ditch in South Korea back in the 1980s. For the most part the impact was survivable but the post impact fire resulted in severe thermal injuries and multiple fatalities to crew and passengers.
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How about using the aircraft as a tool to achieve an aim. Utilising the full flight envelope (and occasionally beyond the flight envelope in combat situations) upto and including max weights in hostile environments both in terms of weather and situation.
Most civilian operators place strict 'wear and tear' usage limits on their machines that the military do not.
p.s. We used to practice auto rotation to a running landing in the S61 all the time!
Most civilian operators place strict 'wear and tear' usage limits on their machines that the military do not.
p.s. We used to practice auto rotation to a running landing in the S61 all the time!
Last edited by Wirbelsturm; 28th Jun 2013 at 07:58. Reason: Speeling!
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Wirbelsturm,
Negative.
Limits are not to be exceeded.
Unless you have ****** up! If you have not planned correctly, for speed, time, location.....then you need to exceed limitations.
If you plan.....And the whole world breaks loose....different
Negative.
Limits are not to be exceeded.
Unless you have ****** up! If you have not planned correctly, for speed, time, location.....then you need to exceed limitations.
If you plan.....And the whole world breaks loose....different
Ralphmalph is correct. Limitations are just that, limitations and are not to be exceeded. Military aircraft component overhaul times and lives are computed based on an aircraft usage spectrum that is negotiated between the military customer and the manufacturer. This is one area that tends to get complex when the actual usage spectrum differs from the one originally negotiated or changes throughout the life of the vehicle. As an example, the negotiated usage spectrum may call for one autorotative descent every 4 flight hours when in actuality an aircraft assigned to a training outfit may do many times that in the course of its life. This example was sighted as the cause for the premature failure of main gear box free wheeling units in aircraft used for training.
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ralphmalph,
I don't believe any pilot 'plans' to exceed any limitations neither did I intimate such. The likelihood of transgressing a limit is always going to be greater when operating at a reduced margin toward that limit.
For example I broke the MRGB twin engine torque limit during a SAR pickup in the lake district many years ago. The weather was extreme with high winds and a pickup from 20m below a ridge line which was 90 degrees to the wind leading to extreme turbulence above the pickup site. Despite thorough planning and using smoke to show the demarcation line a sudden squall placed the aircraft below the turbulent boundary layer and the torque required to recover the rate of descent prior to impacting the hill was higher, transiently, than the twin engine torque limit.
No amount of planning could have predicted the situation.
The upshot was to return the aircraft to base, SOAP analysis of the MRGB and dropping of the mag plugs for inspection.
The danger occurs when crews accidentally transgress limits but then don't report them. Then other crews operating the aircraft after the event reap the repercussions, not the original crew.
I don't believe any pilot 'plans' to exceed any limitations neither did I intimate such. The likelihood of transgressing a limit is always going to be greater when operating at a reduced margin toward that limit.
For example I broke the MRGB twin engine torque limit during a SAR pickup in the lake district many years ago. The weather was extreme with high winds and a pickup from 20m below a ridge line which was 90 degrees to the wind leading to extreme turbulence above the pickup site. Despite thorough planning and using smoke to show the demarcation line a sudden squall placed the aircraft below the turbulent boundary layer and the torque required to recover the rate of descent prior to impacting the hill was higher, transiently, than the twin engine torque limit.
No amount of planning could have predicted the situation.
The upshot was to return the aircraft to base, SOAP analysis of the MRGB and dropping of the mag plugs for inspection.
The danger occurs when crews accidentally transgress limits but then don't report them. Then other crews operating the aircraft after the event reap the repercussions, not the original crew.
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I don't believe any pilot 'plans' to exceed any limitations
you'll see stories about them here, there and elsewhere.
Mini....just how does one "dodge" Rounds? I know the Brits do that by quaffing back a half dozen Pints bought by others then looking at their Breitling and muttering something to the effect they "must be off" and "Cheerio!".
1. Not having a foreign policy developed by a recovering alcoholic, who couldn't point to America on a map [of America].
2. Listening to the J2 brief.
3. Not flying at 80 Kts and 300 feet, using the same ACP's day in day out.
4. 3D manouvering instead of 2D thinking.
ralph & minigun: two zero value posts. Please pat yourselves on the back. (And whomever wound you up ... was that SASless? )
Jack: good point on life limits and the wear and tear training aircraft experience. However, when we compare where this discussion has gone since the stupid question that started it (see the title) I wonder why the mods don't just shut it down.
The initial dumb question has been answered.
Military aircraft have to autorotate, and military pilots both practice autorotation, and train for autorotation.
Likewise with civil helicopters and pilots.
Maybe this thread needs to be closed.
Jack: good point on life limits and the wear and tear training aircraft experience. However, when we compare where this discussion has gone since the stupid question that started it (see the title) I wonder why the mods don't just shut it down.
The initial dumb question has been answered.
Military aircraft have to autorotate, and military pilots both practice autorotation, and train for autorotation.
Likewise with civil helicopters and pilots.
Maybe this thread needs to be closed.
Last edited by Lonewolf_50; 1st Jul 2013 at 18:19.
