Parachute for Choppers!!!
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Parashute for Choppers!!!
I am thinking of a new idea for helis...
What about having a parashute being deployed from the center of the rotors if the engine should fail so as to bring the chopper down to the earth safely.
Has this idea been done before or does anyone have any ideas why it would or would'nt work.
Any advice appreciated.
What about having a parashute being deployed from the center of the rotors if the engine should fail so as to bring the chopper down to the earth safely.
Has this idea been done before or does anyone have any ideas why it would or would'nt work.
Any advice appreciated.
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I can't fault your enthusiasm...
Does anybody else get a shudder when someone refers to a helicopter as "Chopper?" 
Anyway, I believe this was investigated by the Army decades ago and moth-balled. I'm sure Lu Z or Rich L can elaborate more. Try contacting the folks below and see if they have any records available...
U.S. Army Aviation Safety Board
I don't believe it would be practical. There are too many variables that you would not be able to control in an uncontrollable situation. Also, the blades would need to be at zero rotation less they steel air from the canopy or get tangled in extreme attitudes.
I guess it would be practical if ship were in blow-back where the helicopter is a giant lawn dart! Also, speaking as a former Jump Master, the aerodynamics and capabilities of parabolic parachutes are limited. Too much airspeed or weight when deployed, and you will rip the gores right out of the package. If the helicopter experiences complete failure with blow-back, the kenetic energy created with mass and speed will be too great - - even for ballistic heavy drop parachute configurations.
Besides, these types of parachutes are complicated... and they don't always work! I can't tell you how many times I've seen a jeep or a tank burn in... amazing site. Small systems for LIGHT fixed wing aircraft and ultralights are successful because they don't need to be complicated and weight isn't as much a factor. What you propose is quite the opposite. Good luck!
Anyway, I believe this was investigated by the Army decades ago and moth-balled. I'm sure Lu Z or Rich L can elaborate more. Try contacting the folks below and see if they have any records available...U.S. Army Aviation Safety Board
I don't believe it would be practical. There are too many variables that you would not be able to control in an uncontrollable situation. Also, the blades would need to be at zero rotation less they steel air from the canopy or get tangled in extreme attitudes.
I guess it would be practical if ship were in blow-back where the helicopter is a giant lawn dart! Also, speaking as a former Jump Master, the aerodynamics and capabilities of parabolic parachutes are limited. Too much airspeed or weight when deployed, and you will rip the gores right out of the package. If the helicopter experiences complete failure with blow-back, the kenetic energy created with mass and speed will be too great - - even for ballistic heavy drop parachute configurations.
Besides, these types of parachutes are complicated... and they don't always work! I can't tell you how many times I've seen a jeep or a tank burn in... amazing site. Small systems for LIGHT fixed wing aircraft and ultralights are successful because they don't need to be complicated and weight isn't as much a factor. What you propose is quite the opposite. Good luck!
The word "chopper" is probably quite apt in the context - unless the design is utterly foolproof it's probably what will happen to the parachute !
I've flown with light aircraft systems a few times, and dealt with the design of a couple of trial installations. Whilst I agree that they're pretty simple, they're also remarkably lightweight. Something like this would handle the speed and energy (if not the rotor) of a typical small helicopter and masses 34 lb.
You could blow the rotors off of-course, but that's arguably a little extreme.
G
I've flown with light aircraft systems a few times, and dealt with the design of a couple of trial installations. Whilst I agree that they're pretty simple, they're also remarkably lightweight. Something like this would handle the speed and energy (if not the rotor) of a typical small helicopter and masses 34 lb.
You could blow the rotors off of-course, but that's arguably a little extreme.
G
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A novel approach...
Take a look at this...
http://www.helis.com/types/comultra.php
Click on "Eagle's Perch" in the middle of the page (scroll down). The Eagle's Perch is a twin engine, coaxial pendulum kit helicopter with no tail rotor. Original concept was for Ag spraying, pipe line inspection, and mustering cattle. The blades are made of wood.
The aircraft can maintain flight on a single engine, but it cannot hover without both engines running. There is a ballistic parachute to provide an extra margin of safety.
In an emergency, a steel chain (attached to a parachute) is shot from the aircraft. When the parachute deploys, the wooden blades are cut off from the rotor head by the steel chain!
Okay, who wants to be the test pilot for this one?
http://www.helis.com/types/comultra.php
Click on "Eagle's Perch" in the middle of the page (scroll down). The Eagle's Perch is a twin engine, coaxial pendulum kit helicopter with no tail rotor. Original concept was for Ag spraying, pipe line inspection, and mustering cattle. The blades are made of wood.
The aircraft can maintain flight on a single engine, but it cannot hover without both engines running. There is a ballistic parachute to provide an extra margin of safety.
In an emergency, a steel chain (attached to a parachute) is shot from the aircraft. When the parachute deploys, the wooden blades are cut off from the rotor head by the steel chain!
Okay, who wants to be the test pilot for this one?
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Why would a parachute be better than an autorotating rotor system anyway?
It would be non-controllable at the bottom of the descent in any event and result in a firmer touchdown than a properly flown auto.
It would be non-controllable at the bottom of the descent in any event and result in a firmer touchdown than a properly flown auto.
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A rotor system makes a great alternative to a parachute. It has controllable lift, can be easily steered, and allows forward speeds far higher than a parachute thus allowing for greater flexibility in choosing a landing sight.
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This post reminds me of my time in the Royal Navy, we actually took delivery of parachutes for Merlin crews, apparently due to loss of tail rotor drive in flight. The idea was that above a certain height, if something catastrophic happened, you stopped the main rotor and got the hell out.
Nobody actually cared about the ship, thats replaceable.
To the best of my knowledge, the system was never used.
Nobody actually cared about the ship, thats replaceable.
To the best of my knowledge, the system was never used.
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I heard that the system WAS used.
Some of the pilots parachuted right out of the Navy.
Some of the pilots parachuted right out of the Navy.
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Robinson parachute
In view of the fact that light rotorcraft appear to chop their rotors into the tails more often than more robust machines,and given that in most instances either one or both blades depart the aircraft. Would not a ballistic chute be a nice thing to have? Even if shot from under the belly! Coming down upside down is surely an acceptable option to the alternative.
The device itself would mass around 20kg (50lb) and could be mounted below the aircraft - that's achievable. Certainly they exist for much higher inertia aircraft than an R22. Costwise, you're certainly looking below £6k/$10k, which isn't a great deal compared to the cost of any helicopter.
Operating it could be solved in a similar way to the Yak-38 "Forger", a Soviet harrier copy that sat on a tripod of three gas-turbine engines. If you lost a single engine (I'm not sure how this was sensed, but I'd guess a comparison of N1 values combined with a weight on wheels switch) the ejection was automatic. I believe that the red-navy's record was that about 2/3 of their (fairly large) number of Yak-38 ejections were automatic. (Must be a bit of a shock to the system, but better than the alternative).
In a helicopter, an RPM drop sensor combined with a weight-on-skids switch would probably do the job and be fairly easy to mechanise.
A much more difficult problem may well be the integrity of the suspension loom. It's fairly common in FW applications to mount the parachute and it's ballistic drogue in a canister below the belly of the aircraft. But, then the suspension loom needs to be routed round the side of the aircraft to a suitable attachment - in an R22 I'd venture that the gearbox assembly would probably be that. So, the chute fires out the side, swings round the top, and the aircraft then descends to impact on the wheels or skids - the only bit of structure designed to take a hard ground impact without killing the occupants. The fact is however, that this loom will have to be man-enough to take impact with the rotor without being weakened sufficiently that it breaks under the shock load of a falling aircraft at one end and an opening parachute canopy at the other, or without being wrapped into a still rotating rotor and bringing the canopy in with it. There are looms available that will go through a rotating propeller and survive - but a helicopter rotor is a much more daunting prospect and this would be an "interesting" engineering problem to solve.
So, I think (and incidentally, I'm the bloke who wrote the UK's civil rules for fitting these things onto FW aeroplanes) it's possible.
The other question is - is there any point? As has been pointed out, a competent helicopter pilot should be able to auto to the ground anyhow. If the aircraft is routinely operating over terrain where this isn't feasible - say forrested mountainside, shouldn't they be operating a multi-engine helicopter anyhow? Of course it would save your bacon in the event of a structural failure of, say, a main rotorblade - but is that a realistic risk that needs to be guarded against?
In the fixed wing world, there are two main environments that they are used in - the Cirrus which has never been shown to recover from a spin, and in German where it's mandated for microlights (but their structural rules are such that structural failures are I'm afraid quite common). Most of the rest of the world either has high enough structural standards, or insists upon a spinning evaluation, or both. I'd regard any suggestion of fitting ballistic parachutes to helicopters in that light - where's the need?
That said, they have their uses. In light fixed wing flight testing (my mastermind specialist subject) it's an elegant safety solution for high risk trials such as stalling or spinning of a new prototype. But the occasions where they are really a good idea are few and far between.
G
Operating it could be solved in a similar way to the Yak-38 "Forger", a Soviet harrier copy that sat on a tripod of three gas-turbine engines. If you lost a single engine (I'm not sure how this was sensed, but I'd guess a comparison of N1 values combined with a weight on wheels switch) the ejection was automatic. I believe that the red-navy's record was that about 2/3 of their (fairly large) number of Yak-38 ejections were automatic. (Must be a bit of a shock to the system, but better than the alternative).
In a helicopter, an RPM drop sensor combined with a weight-on-skids switch would probably do the job and be fairly easy to mechanise.
A much more difficult problem may well be the integrity of the suspension loom. It's fairly common in FW applications to mount the parachute and it's ballistic drogue in a canister below the belly of the aircraft. But, then the suspension loom needs to be routed round the side of the aircraft to a suitable attachment - in an R22 I'd venture that the gearbox assembly would probably be that. So, the chute fires out the side, swings round the top, and the aircraft then descends to impact on the wheels or skids - the only bit of structure designed to take a hard ground impact without killing the occupants. The fact is however, that this loom will have to be man-enough to take impact with the rotor without being weakened sufficiently that it breaks under the shock load of a falling aircraft at one end and an opening parachute canopy at the other, or without being wrapped into a still rotating rotor and bringing the canopy in with it. There are looms available that will go through a rotating propeller and survive - but a helicopter rotor is a much more daunting prospect and this would be an "interesting" engineering problem to solve.
So, I think (and incidentally, I'm the bloke who wrote the UK's civil rules for fitting these things onto FW aeroplanes) it's possible.
The other question is - is there any point? As has been pointed out, a competent helicopter pilot should be able to auto to the ground anyhow. If the aircraft is routinely operating over terrain where this isn't feasible - say forrested mountainside, shouldn't they be operating a multi-engine helicopter anyhow? Of course it would save your bacon in the event of a structural failure of, say, a main rotorblade - but is that a realistic risk that needs to be guarded against?
In the fixed wing world, there are two main environments that they are used in - the Cirrus which has never been shown to recover from a spin, and in German where it's mandated for microlights (but their structural rules are such that structural failures are I'm afraid quite common). Most of the rest of the world either has high enough structural standards, or insists upon a spinning evaluation, or both. I'd regard any suggestion of fitting ballistic parachutes to helicopters in that light - where's the need?
That said, they have their uses. In light fixed wing flight testing (my mastermind specialist subject) it's an elegant safety solution for high risk trials such as stalling or spinning of a new prototype. But the occasions where they are really a good idea are few and far between.
G
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I've thought about the parachute thing too. Also thought about wings that could be instantly deployed in emergencies. How about some kind of sprung loaded, telescopic assembly shooting out either side from underneath the aircraft? Might it create enough lift to glide down?
(Then there's always the anti-gravity machine to install...)
We know that flying rotorwings is inherently unstable but it would be interesting to know if any 'slightly unorthodox' safety features have been tried and with what results.
(Then there's always the anti-gravity machine to install...)
We know that flying rotorwings is inherently unstable but it would be interesting to know if any 'slightly unorthodox' safety features have been tried and with what results.
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hi everybody, i apologize in advance for my Frenglish, "tolerance is the policy of the brave"
i m a "dreamer" dreaming in building my own chopper, i ll tell more if someone is interested.
i m also on rotaryforum, for gyros, and rised the subject of BRS parachutes in a gyro.
it appears that no one can agree about it s real utility, its mounting and deploying...
mast mounting ? useless if buntover, or inverted position.
at low altitides... quite useless..
tail mounting ? could be ok
personnally i believe a parachute should be mounted in front, but fired from side, makin heli have a kind of "flat spin" and landing it on the tail, the tail acting as a shock absorber...
thank you
victor
i m a "dreamer" dreaming in building my own chopper, i ll tell more if someone is interested.
i m also on rotaryforum, for gyros, and rised the subject of BRS parachutes in a gyro.
it appears that no one can agree about it s real utility, its mounting and deploying...
mast mounting ? useless if buntover, or inverted position.
at low altitides... quite useless..
tail mounting ? could be ok
personnally i believe a parachute should be mounted in front, but fired from side, makin heli have a kind of "flat spin" and landing it on the tail, the tail acting as a shock absorber...
thank you
victor
I'm told that a Larry Neal in Texas had a BRS fitted onto a tandem Air-Command at some point (personally I'm not sure I'd fly an Air Command with a chute!, and certainly not without). I know no more than that, but it might be worth seeing if you can track him down.
I disagree with you about descending onto the tail - the whole aircraft structure is designed to absorb loads when it comes down on the maingear, and redesigning other parts for the same purpose is just going to add weight and complexity for no good reason.
G
I disagree with you about descending onto the tail - the whole aircraft structure is designed to absorb loads when it comes down on the maingear, and redesigning other parts for the same purpose is just going to add weight and complexity for no good reason.
G
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Apparently, Nick L knows test pilots who've bailed out of uncontrollable machines...
I think the point about parachutes is for when an autorotation isn't possible.
As for making the airframe stronger should the aircraft land on it's tail, wouldn't it make sense to have it act as a crumple zone, assuming the chute had slowed down the descent to acceptable levels?
(sorry to bring this back up, posted the above in more recent thread)
I think the point about parachutes is for when an autorotation isn't possible.
As for making the airframe stronger should the aircraft land on it's tail, wouldn't it make sense to have it act as a crumple zone, assuming the chute had slowed down the descent to acceptable levels?
(sorry to bring this back up, posted the above in more recent thread)
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Apparently, Nick L knows test pilots who've bailed out of uncontrollable machines...
I think the point about parachutes is for when an autorotation isn't possible.
As for making the airframe stronger should the aircraft land on it's tail, wouldn't it make sense to have it act as a crumple zone, assuming the chute had slowed down the descent to acceptable levels?
(Posted above in old thread by RDRickster... oops!)
I think the point about parachutes is for when an autorotation isn't possible.
As for making the airframe stronger should the aircraft land on it's tail, wouldn't it make sense to have it act as a crumple zone, assuming the chute had slowed down the descent to acceptable levels?
(Posted above in old thread by RDRickster... oops!)
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hi Gengis an others, thank you for discussing.
hi rickster, sorry, i m new here, and dint see the previous thread
here is the thread i picked from Rotaryforum
http://www.rotaryforum.com/forum/showthread.php?t=2261
as you can see it was a yes-no debate more than a finding-solutions one
you said the airfrane is designed for loads under the mast... ok, but a chute can have several strong wires drowed in the airframe and linked to the strongest part of the frame, ok it sould destroy or deform cockpit but i still thinking like Col the tail is a perfect crumple zone and while the shock, pilots and occupants are lying on their back..
i must say i m not an engineer, so sorry i m just an enthusiast
thank you all
hi rickster, sorry, i m new here, and dint see the previous thread
here is the thread i picked from Rotaryforum
http://www.rotaryforum.com/forum/showthread.php?t=2261
as you can see it was a yes-no debate more than a finding-solutions one
you said the airfrane is designed for loads under the mast... ok, but a chute can have several strong wires drowed in the airframe and linked to the strongest part of the frame, ok it sould destroy or deform cockpit but i still thinking like Col the tail is a perfect crumple zone and while the shock, pilots and occupants are lying on their back..
i must say i m not an engineer, so sorry i m just an enthusiast
thank you all
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re : hello world, i apologize for my bad Frenglish
i m inerested in chutes in a gyro or ultralight choppers,
i m a mad dreamer
who plans to build one, ok ok dont throw stones please, i have a full truck of them
as you can guess, i d like to have a chute if someday i plan to test any rotor aircraft.
so i must precise this : i think on a chute in extreme cases
avoiding autorotation like :
loss of a blade, structural failure, tail failure, mast bumping, destructive vibrations, flip in wind gusts , and others
, ok autorotation is better than a chute, when you can....
as i said in the other thread, i wonder if the chute could no be fired from the nose, sideways, linked to the strongest part of the airframe by steel wires (drowned in the fuselage), then this would create a "violent" flat spin but keep away the chute wires from the rotor, put the chopper in a nose-up attitude and land it on the tail that could act as a shock absorber...
another question, is there a model of BRS or other chute specially designed for mast mounting?
just throwing hairbrained ideas
thank you
victor
i m inerested in chutes in a gyro or ultralight choppers,
i m a mad dreamer
who plans to build one, ok ok dont throw stones please, i have a full truck of them as you can guess, i d like to have a chute if someday i plan to test any rotor aircraft.
so i must precise this : i think on a chute in extreme cases
avoiding autorotation like :
loss of a blade, structural failure, tail failure, mast bumping, destructive vibrations, flip in wind gusts , and others
, ok autorotation is better than a chute, when you can....
as i said in the other thread, i wonder if the chute could no be fired from the nose, sideways, linked to the strongest part of the airframe by steel wires (drowned in the fuselage), then this would create a "violent" flat spin but keep away the chute wires from the rotor, put the chopper in a nose-up attitude and land it on the tail that could act as a shock absorber...
another question, is there a model of BRS or other chute specially designed for mast mounting?
just throwing hairbrained ideas
thank you
victor
Au contraire...
...I seem to remember a "bunch" of FTEs and TPs bailing out from one of the prototype Merlins that crapped itself at altitude - all survived.
P.S. What IS the collective (no pun intended) noun for a group of our Test Pilot/ Flight Test Engineer buddies?........answers on a postcard, please.
P.S. What IS the collective (no pun intended) noun for a group of our Test Pilot/ Flight Test Engineer buddies?........answers on a postcard, please.