It seems like every month or so you are hearing about some helicopters crashing and killing a few soldiers. Then yesterday the US Marine heli went down.
Now a couple of British copters crashed into each other over the gulf and killed 7 more guys.
What is causing this? Are helicopters inherently more dangerous than airplanes? Are they harder to fly or maintain?
What is going on?
Helicopters crash all the time. When I was in the army, I don’t think 2 weeks went by without a crash. I was involved in a near hit myself, with a jet fighter. They’re maintenance-intensive, and the armed forces kill things better than they fix things. Also, I started finding out a couple of years ago just how clueless many helicopter pilots are about things like their rotor wash. (like how much of a threat it is to ultralight aircraft)
There’s a saying in aviation: If the wings are travelling faster than the fuselage, it’s a helicopter, and therefore unsafe.
Yes and Yes
Which doesn’t stop me from riding in helicoptors, for some odd reason.
One other thing to consider is that helicopters operate in much more dangerous conditions than airplanes do. They are expected to fly in, pick up, and drop off troops and eqipment in places an airplane wold have no hope of landing in.
Ahem! [sub]Geez, you sound like my father: “How could anyone be so stupid as to fly something with such an unstable wing? Ah my son, my son!”[/sub]
This is true. Helicopters operate fairly low – “nap of the earth” when the army flies them. There is something called the “height-velocity diagram” – also known as the “dead man’s curve” – that shows the safe envelope for low altitude helicopter flight. If you have enough altitude but not enough speed, or if you have the speed but not the altitude, you will be unable to safely autorotate in case you lose your engine. There are some missions – even in civilian flight training – where you have to operate outside of the height-velocity envelope; but the risks are small, and you’re not there for long. In the case of military aviation, pilots are often outside of the envelopes for a greater amount of time; for example, flying long legs at fifty feet and 120 knots. (Note: I haven’t actually seen the H-V diagram for any military helicopters, so I don’t know the extent of the envelope.)
Flying_Monk is right, that aircraft crash all the time. Not so often, it seems, in the civilian world, but in the military world. We’re all focused on the military usage right now, so they are more noticeable. FWIW civil aviation is very very safe, and most crashes are not fatal.
Wasn’t the Marine helicopter crash originally reported as being caused by small arms fire? Back during the Balkan War, I noticed several ‘enemy fire’ --> ‘accident’ transformations, which makes me wonder about the guys that our airmen take orders from.
Broomstick: Do you have a cite for helicopters being less safe than airplanes? I seem to remember reading a few years ago that the safest single-engine aircraft was the Bell JetRanger.
Stinkpalm: Are they harder to fly and maintain? They’re certainly more maintenance-intensive than airplanes. More moving parts, more stress on the parts, etc. But are they harder to fly?
Interesting question. I first learned to fly in fixed-wings, then started flying helis much later. It’s a difficult question to answer. Let’s say you have an airplane that is “perfectly” trimmed, and you have an unlimited amount of space. You push the throttle forward and do nothing else. The airplane could conceivably take off, fly until it runs out of fuel, and land all on its own. People do it all the time with models.
On the other hand, a helicopter needs constant, minute control inputs. Assuming you had a helicopter that was stable enough (NB: helicopters are inherently unstable), it might rise into the air on its own and not crash. It might fly until it ran out of fuel. But there are definite control inputs that must be made so that a powerless helicopter can enter and maintain autorotation (the helicopter equivalent of a glide). The unpowered, uncontrolled landing is irrelevant though, since unlike a fixed-wing aircraft a helicopter can’t take off and fly on its own in the first place.
But is it harder to fly a helicopter? The constant control inputs become – indeed must become – subconscious. The best way to get the hang of them is to not think about them. It’s rather Zen. The learning curve in a helicopter is a little steeper than in an airplane. I think the hardest part of flying an airplane is landing, and you learn that after your first take-off and cruise. The hardest part of flying a heli is hovering, and that’s the first thing you learn.
This is how I learned to hover: My instructor told me to keep the nose of the helicopter pointed at a point. He’d handle everything else, while I handled the anti-torque pedals. Simple, no? No! I couldn’t keep the nose straight to save my life! An airplane has spring-loaded rudder pedals because you return the rudder to centre after your turn. Anti-torque pedals are not spring-loaded because you want them to stay put once you’ve made inputs to counteract the torque caused by your throttle setting. Since they are not spring loaded, you have to “dance” on them at first to get the hang of where they should be.
Just as I was able to keep the nose straight, the instructor told me to take the collective and throttle and keep an altitude and keep the nose straight. Since I was still dancing a bit on the pedals I was changing the amount of power sent to the main rotor, which meant I was changing the altitude which meant I had to move the collective lever, which changed the amount of torque, which required me to move the pedals. There’s a reason the instructors joked that you have to learn to juggle before you could fly a helicopter.
I finally just got the hang of that, when the instructor said Ihad to take the cyclic. At the end of an hour I was hovering, keeping the helicopter pointed into the wind and more or less over one spot. It was rather like standing on top of a bowling ball and trying to “walk” it across the floor.
But I soon got the hang of it (much to the chagrin of a friend of mine who was flying in the army and said that most people in her class took much longer to hover – but hey, I was paying for this).
Once hovering was out of the way, the rest of the training was easy. (It did take me a while to stop trying to “flare to a stall” like I did in the Cessna, and to level the skids before I stopped moving forward.) Compared to a Robinson R-22, a Cessna 172 handles like a pig. The R-22 and the Schweizer 300CB are very light on the controls compared to the Cessnas, Grumman and Piper I’ve flown.
You definitely have much more going on in a helicopter, control-wise. But is it harder to fly a fling-wing? I’d say it isn’t. It’s just “different”. Is it harder to eat a steak; or an orange? It’s different.
How’s this, Johnny? It’s more difficult to learn to drive than it is to learn to ride a bike, but is it really difficult to drive a car? Anyone can do it, you just have to learn more.
Do helicopters have any sort of autopilot?
Flying_Monk: I don’t know. I don’t find it at all difficult to fly either a helicopter or an airplane. The most difficult part is finding the time or money to do it. I think an airplane pilot would find it more difficult to learn how to fly a helicopter. (I mentioned the hurdle I had with the landing flair.) On the other hand, I think a helicopter pilot would find it similarly difficult to learn to fly an airplane. So I still don’t think either is “harder” than the other; it’s just what you’re used to.
Icerigger: Some helicopters have autopilots; but as with all aircraft, you need to learn how to fly them before an autopilot will do you any good.
One big difference between helicopters and airplanes is that the step-up from a “training” helicopter is a turbine-powered helicopter. (Usually. Robinson has the R-44 which is actually a little faster than a Bell 206, with four seats instead of the JetRanger’s five.) The step-up from a “training” airplane is a more capable piston-powered airplane. Not all jet helis will have autopilots, while many fixed-wings have them as options.
In a piston-powered helicopter there is a linkage between the collective and the throttle, so that as you raise the collective you don’t have to fiddle with the throttle (as much). There is a governer you can get as an option (such as on a Robinson) that makes power management easier, but your instructor will not let you use it until you’ve managed to control the power without it.
Johnny, please don’t misunderstand. Asking if a helicopter is inherently more dangerous than a fixed wing is like asking if experimental aircraft are inherently more dangerous than factory-certified. Or if a student pilot is inherently more dangerous than a 20,000 hour veteran. The answer is “yes” but to be fully accurate you need a "yes, BUT - " followed by an explanation.
As you yourself pointed out, a heli is inherently UNstable. Unlike an airplane - where I can adjust the trim, power, and even autopilot then neglect the flying duties for entire minutes at a time if required - you have to be on top of that rotorcraft at all times without exception as you pointed out. This is sometimes a GOOD thing - military fighter airplanes are ALSO inherently unstable by design. It is part of what makes helicoptors so very nimble and versitle. But it does require that constant attention that’s the “inherent danger”. They can be exceedingly UNforgiving of any sort of mistake or malfunction.
There are also items like rotors vs. fixed wings. Without power fixed wing aircraft do glide nicely, and indeed sailplanes have no engines yet they fly. In rotorcraft those blades HAVE to move, and when the engine quits you go down quick and sometimes quite hard. In an engine failure you basically land on what you’re above - a fixed wing may have more options in many situations. And then, if you break a prop blade in flight in a fixed wing your chances of survival are MUCH higher than having heli rotor depart in flight (in that case - you aren’t surviving from what I understand)
Like any other form of flying, flying helicoptors involves learning the risks and how to manage them. Because that skill varies so widely among pilots it tends to overwhelm the inherent characteristics of the aircraft to a large degree. Thus, a well-flown helcioptor (i.e. good pilot) is actually safer to be in than a badly flown fixed wing. Although “catastrophic failure” of a rotorcraft part may have greater consequences (on average) than in a fixed wing, this can be offset by diligent attention to maintenance. In other words, a well maintained heli is safer than a poorly maintained fixed wing. There is also the manner of flying. Fixed wing flying is generally pretty safe - but crop dusting is a much riskier form of such flying, as is banner towing. As is combat flying, operating off an aircraft carrier, and so forth. For someone operating a heli within the proper envelope 99% of the time a heli probably is just as safe as a fixed wing, all other things being equal. But a lot of helicoptor flying is NOT within that envelope, and any time you step outside it the risks go up. And a LOT of chopper flying is outside that safe zone - construction, military operations, etc. The ability to fly low, hover, and so forth is part of why helicoptors are so damn useful. And fun.
So no, I don’t have a cite, just a feeling, but it’s also a refelction of what rotorcraft friends and acquaintances have told me. If there are risks they can certainly be offset by training, practice, proper maintenance, and good judgement - just like in any other form of flying. On the whole, chopper pilots have also struck me as more attentive to details - because they HAVE to be. You can be pretty out of it and still get a Cessna off the ground and back on again - but I don’t know any clueless rotorcrafters.
Or, to extend the analogy - fixed wing flying is inherently more dangerous than driving a car. But the vast majority of pilots will NOT die in a plane crash but of something else. Why? Because training, skill, and good judgement off set the risks involved. Frankly, I’m much more afraid to drive down the freeway than fly through the skies - because so many auto drivers are… are… well, this isn’t the Pit, let’s just say they’re stupid and clueless and ignorant of physics and leave it at that.
The problem with military aviation - and not just the heli’s - is that you are engaged in activities that, by civilian standards are crazy-dangerous (such as flying at high speed at low altitude at night without lights) AND, in war, you ALSO have to worry about people who are seriously trying to kill you. All of which makes military aviation, on a certain level, inherently more dangerous than civilian aviation. Because the nature of the job demands it. That doesn’t mean the military pilots are stupid or incompetant - on the contrary, they are the best at what they do because only the best are capable of doing what they do. Their skill and training offsets the inherent danger, reducing the total danger, which is really the danger you have to worry about.
Now, go back to fixed-wing vs. helicoptors: military missions for fixed wings include fighters and bombers - who often have the option of flying high, thereby evading obstacles, avoiding some of the shooting, and they have more time and options to deal with malfunctions should they occur. Including having the option (in some birds) of ejecting. Contrast this with helicoptors: they fly low, within range of enemy fire, they’re often operating outside of a “safe enevelope” due to what they’re trying to accomplish, and because of that, if something DOES go wrong there may not be time or options available to do something about that. All of that has driven the technology behind better and more reliable engines and parts for helicoptors, better maintenance schedules, better training, and all the other components of risk reduction.
A Bell JetRanger MAY be the safest single-engine aircraft statistically, but it also costs a heck of a lot more than a fixed-wing single and requires more intensive maintenance. Is that bad? No - of course not. No point in having an aircraft if you don’t operate it safely.
I guess what I’m saying is that something can have an inherent danger yet still be handled safely. Which is why I like to ride in helicoptors with pilots I know and trust - I feel that the situation overall is a reasonable risk.
An excellent post, Broomstick; especially your paragraph on the roles typically undertaken by helicopters that often put them into flight regimes that are outside of the envelope, and your elaboration on the dangers of military flying.
You have made a forced landing, and I have not. But I have a feeling I’d rather lose power in a helicopter. While you point out correctly that you pretty much land on the terrain you’re over, helicopters have a big advantage: They don’t need a runway. Given a few knots of wind a helicopter can “zero out” – land at a zero rate of descent (assuming the pilot plays the collective just right) and zero forward speed. I’d much rather put a helicopter down in a parking lot than trying to land a fixed-wing on one of the freeways around here! But as I said I’ve never made a forced landing, either in a heli or a fixed-wing.
As for a “safest single-engine aircraft” cite, this is what I found:
From Aviation Today:
[quote]
The JetRanger is typically known as the safest single-engine aircraft (including all single-engine airplanes). It’s more forgiving and has a proven 32-year record of reliability. But don’t think for a second that you can’t get killed in one. Remember that most accidents are not caused by mechanical failures, but by failures in judgment.
[quote]
From Helitech:
Note the first quote. I think it backs up nicely your assertation that “if there are risks they can certainly be offset by training, practice, proper maintenance, and good judgement”.
There were supposed to be two quotes up there, but you can see I forgot a slash. So much for “On the whole, chopper pilots have also struck me as more attentive to details”! 
:o
" "
:smack:
Would it make you feel better if I told you about the simpleton screw-ups I made today during my flying? Maybe I should have said “more attentive to detail while flying”?
Certainly one of the attributes of a good pilot - of anything - is a joy in chasing perfection. Note I said chasing - we all know we’ll never catch it, but the it’s a pursuit that’s worthwhile anyhow.
Your statement about the forced landing sceanario makes some good points. When I had my forced landing I was over farmland, which provides many options to a prepared pilot. If you’re over a city, though, particularly in a heavily built-up district, then yes, a forced landing in a helicoptor may, in fact, be safer than an attempt in a fixed wing. So much depends on the terrain you’re over, and the options you have at the time.
Which is part of the challenge of flying - you’re dealing with the real world with all it’s complexities and complications.
Wouldn’t mind rotor lessons, but just can’t afford them right now - not in a way that would do it right. So I spend my money on being a better fixed-wing pilot.
