Why are helicopters so expensive?

[PLAGUEz]

I've always thought it's really the engine you're paying for, considering I've seen helicopter accidents on youtube ad the airframe seems to break fairly easily. Anyone have insight into this?

[Lizzard]

I guess they design "lighweight" Helicopters to increase the performance..

[xxJohnxx]

Well, the engine sure is expensive, but probably the most expensive part of the helicopter is what is powered by it.

 

On a normal jet (the A-10 for example) you have the compressor, which compresses the air, mixes it with fuel and ignites it. The hot air then flows through a turbine which is basically a "windmill" (simplified a bit for explainatory purposes). This turbine is directly connected to the fan. The turnning fan provides approxematly 80% of the jet engines thrust, while the core provides 20%.

The mechanical layout therefor is relativly simple. You have two (or three) undependent axes, rotating at diffrent speeds, connected by fast moving air basically. There are normally no gears involved (there are some gears for devices powered by the engine, but that goes to far for now).

 

Have a look at this picture:

 

http://upload.wikimedia.org/wikipedia/commons/c/c0/Turbofan_operation.png

 

It should give you an idea of what I tried to explain :).

 

Now, the helicopter engine/gearbox on the other hand is much more difficult. You have the same compressor as the jet engine has, however everything behind that is diffrent. In the Ka-50 for example, the same compressor still blows air at the turbine. This turbineis not connected to a fan, however instead it is connected to a gearbox.

In the Ka-50 for example, this is not so easy, because the gearbox is between the engines. The driveshaft, comming out the back of the engine therefor has to be deflected with, you guess it, another (intermediate) gearbox (or two, because the Ka-50 has two engines).

The gearbox(es) are difficult to make parts as well. You need to transmitt hughe forces at high rpms, while having the most lightweight built possible.

Gears create heat, they need oil, that oil needs cooling. Expensive...

However, once the power has found its way through the gearbox, more expensive parts lay ahead.

 

The rotor mast assembly. There is a lot of mechanics involved in makinging the blades seperatly adjust their angle of attack within the rotation (cyclic), and at the same time having all of them adjust their angle of attack togheter (collectiv). Lot's of oil and hydraulics are needed to keep that stuff from falling of...

 

After that, you need the rotor blades. With the composite materials, heating elements and other gimmics used today they aren't cheap either.

 

Then you often also need dampers, stabilators and other gimmicks to even be able to controll it (though this is also true for modern aircraft, directly compared probably not to the same extend though).

 

But that's not finished there yet. Deppending on the load, etc. your rotor rpm will vary. Now you need (mechanical or electrical) governors, which will keep the rotor at a speed where it is fast enough to create lift and slow enough not to fall appart.

 

So to sum it up: The main reason why a helicopter is so expensive over an aircraft is the ammount of mechanics needed to transmitt the power from engien to the air.

 

Hoping that was some help!

 

John

Edited March 16, 2014 by xxJohnxx
Changed up the use of turbine and compressor!

[AlphaOneSix]

When you buy a helicopter, you are also purchasing all of the R&D that went into developing it.

[joey45]

They are expensive cos it's 1000s of components working in perfect harmony...

[Cp]

They are expensive cos it's 1000s of components working in perfect harmony...

 

Perfect harmony? I thought helicopters were just a a bunch of loose rotating parts flying in close formation? :D

[xxJohnxx]

Perfect harmony? I thought helicopters were just a a bunch of loose rotating parts flying in close formation held together by hydraulics? :D

 

Don't forget the hydraulics. Else they will get into a loose formation :P

[Scrim]

A loose formation, more commonly known as "OH MY GOD OH MY GOD OH MY GOD I DONT WANT TO DIE I DONT WANT TO DIE!!!" :P

[Flagrum]

You all forget the major part of all the costs.

 

Besides all the moving parts that have to work under and with enormous forces while still having to be lightweight, the main component that holds it all together and basically makes a helicopter fly is magic! And you all know how expensive magic nowadays is ...

[Bushmanni]

Material costs of modern high-tech products are pretty negligible compared to work related costs ie. man hours are the main thing you are paying for. Manhours in turn are pretty much related to how exotic materials (takes lots of work to extract, refine and turn in to usable form) are used and how complex the product is to design, manufacture and assemble. This also explains why it's cost effective to build multi billion factories with lots of robots to reduce the amount of workers (like in case of modern CPUs). Helicopters are complex machines built of exotic materials but you can't sell enough of them to justify highly automated multi billion factory.

[Chris1012]

There's also the huge amount of money aviation companies have to squirrel away for when the inevitable goon slams it in doing something silly...

[159th_Falcon]

Well, the engine sure is expensive, but probably the most expensive part of the helicopter is what is powered by it.

 

 

On a normal jet (the A-10 for example) you have the turbine, which compresses the air, mixes it with fuel and ignites it. The hot air then flows through a "windmill" (simplified a bit for explainatory purposes). This "windmill" is directly connected to the fan. The turnning fan provides approxematly 80% of the jet engines thrust, while the core provides 20%.

The mechanical layout therefor is relativly simple. You have two (or three) undependent axes, rotating at diffrent speeds, connected by fast moving air basically. There are normally no gears involved (there are some gears for devices powered by the engine, but that goes to far for now).

 

Have a look at this picture:

 

http://upload.wikimedia.org/wikipedia/commons/c/c0/Turbofan_operation.png

 

It should give you an idea of what I tried to explain :).

 

Now, the helicopter engine/gearbox on the other hand is much more difficult. You have the same turbine as the jet engine has, however everything behind that is diffrent. In the Ka-50 for example, the same turbine still blows air at a "windmill". This windmill is not connected to a fan, however instead it is connected to a gearbox.

In the Ka-50 for example, this is not so easy, because the gearbox is between the engines. The driveshaft, comming out the back of the engine therefor has to be deflected with, you guess it, another (intermediate) gearbox (or two, because the Ka-50 has two engines).

The gearbox(es) are difficult to make parts as well. You need to transmitt hughe forces at high rpms, while having the most lightweight built possible.

Gears create heat, they need oil, that oil needs cooling. Expensive...

However, once the power has found its way through the gearbox, more expensive parts lay ahead.

 

The rotor mast assembly. There is a lot of mechanics involved in makinging the blades seperatly adjust their angle of attack within the rotation (cyclic), and at the same time having all of them adjust their angle of attack togheter (collectiv). Lot's of oil and hydraulics are needed to keep that stuff from falling of...

 

After that, you need the rotor blades. With the composite materials, heating elements and other gimmics used today they aren't cheap either.

 

Then you often also need dampers, stabilators and other gimmicks to even be able to controll it (though this is also true for modern aircraft, directly compared probably not to the same extend though).

 

But that's not finished there yet. Deppending on the load, etc. your rotor rpm will vary. Now you need (mechanical or electrical) governors, which will keep the rotor at a speed where it is fast enough to create lift and slow enough not to fall appart.

 

So to sum it up: The main reason why a helicopter is so expensive over an aircraft is the ammount of mechanics needed to transmitt the power from engien to the air.

 

 

Hoping that was some help!

 

John

 

Good points, though in my opinion not really the reason why a helicopter is so expensive.

For example the intermediate gearbox, its a pretty straightforward thing, much simpler then the (automatic) gearbox of a modern car.

The cooling isn't that much of an issue either, the PT6 is a good example of that.

As for the RPM control, in the old days of the hydromechanical control units it was quite a challenge, these days whit all the electronics is much easier to maintain a given RPM.

 

What make's an helicopter so expensive is that EVERYTHING has to be an EXACT.

Much more so then in planes.

 

And its this precision in each and every component of the helicopter what makes it expensive.

 

To give you an idea, get two pieces of wood. And shape them exactly the same. (within 0.01 mm orso)

Then make sure both have the exact same weight.

Then make sure the lateral center of gravity is exactly the same

then make sure the longitudinal center of gravity is exactly the same.

 

You've just gone trough the basic challenges of manufacturing a rotorblade.

 

 

Another reason is that a helicopter has to deal whit severe vibrations throughout its live.

Making it much harder to design it in a way that it actually stays together.

Edited March 16, 2014 by 159th_Falcon

[Yurgon]

On a normal jet (the A-10 for example) you have the turbine, which compresses the air, mixes it with fuel and ignites it. The hot air then flows through a "windmill" (simplified a bit for explainatory purposes).

 

That's a great explanation! :thumbup:

 

Just a question about the terminology. When you use the term "turbine" in your post, I would call it "compressor", and when you use the term "windmill", I would call it "turbine", just as is shown in the Turbofan operation chart you posted.

 

"turbine" may be a bit more technical than "windmill", but I think it's also a bit more to the point, and I think "compressor" is almost self explanatory, so I wouldn't exchange it with another word.

[xxJohnxx]

Just a question about the terminology. When you use the term "turbine" in your post, I would call it "compressor", and when you use the term "windmill", I would call it "turbine", just as is shown in the Turbofan operation chart you posted.

 

"turbine" may be a bit more technical than "windmill", but I think it's also a bit more to the point, and I think "compressor" is almost self explanatory, so I wouldn't exchange it with another word.

 

Good point! I adjusted my post accordingly! :)

[Griffin]

Parts of course are expensive because of the required precision and the R&D that have been mentioned. Another thing is the certification that can cost around a million for general aviation aircraft. So yeah you're not buying just the material of the part but you're funding the whole process that has taken years prior the introduction to service of the aircraft.

The turnning fan provides approxematly 80% of the jet engines thrust, while the core provides 20%.

That must have been the most detailed explanation to the shortest question I've seen. Kudos for that!

Those thrust figures however are true only static at sea level but at airliner cruise altitudes they are closer to 50:50.

[AlphaOneSix]

So yeah you're not buying just the material of the part but you're funding the whole process that has taken years prior the introduction to service of the aircraft.

 

This should be repeated in case anyone misses it. This is the single biggest cost in anything aviation related. Well, not a single cost, but you get the idea.

[Orava]

When I do helicopter at home, it's priceless.

[outlawal2]

All of the above mentioned points certainly add to the costs, but I think the primary cost involved is LIABILITY and having to offset those costs entailed fighting law suits and preparing FOR the inevitable lawsuits.. It is a litigious world and having spent a lot of time around an R22 I can tell you that the huge cost of that bird is not explained in the mechanics of it...

 

1/4 of a Million Dollars for a smart car with blades is insane... And unfortunate for the industry I am afraid...

[Flagrum]

It's the numbers.

 

The automotive industry has certainly comparable R&D costs and accruals for possible lawsuits. Also the necessary quality of the materials and production processes is not that much different, I would guess. Yes, usually there is more electronics in an a/c than in a car, but that hardly explains the huge price difference.

 

But it is the number of produced units that does. How many R22 are out there? Thousands! But pick any car brand and you will count into the millions.

[AlphaOneSix]

This is how the VH-71 Kestrel price skyrocketed to around $400 million per copy. A ton of R&D work went into it, and that cost was only going to be spread out among 28 aircraft. Like Flagrum said, other industries have the same issues, they just get to spread their costs out over millions of units.

Edited March 17, 2014 by AlphaOneSix

[cichlidfan]

It's not just R&D. Manufacturing/assembly processes are also more costly in small quantities. You don't spend time automating or streamlining any part of the process.

[mvsgas]

Huge cost on simple systems that you would think would be part of the standard also add to the cost.

http://www.robinsonheli.com/rhc_r66_turbine.html

23K for air conditioning? wow

I guess when people have little choices in term of companies making certain products, they are stuck. How many companies build helicopters for the public? Bell, Robinson, AirBus...

[159th_Falcon]

Huge cost on simple systems that you would think would be part of the standard also add to the cost.

http://www.robinsonheli.com/rhc_r66_turbine.html

23K for air conditioning? wow

I guess when people have little choices in term of companies making certain products, they are stuck. How many companies build helicopters for the public? Bell, Robinson, AirBus...

Hughes/Schweizer

Magdonnel Douglas (MD series)

Bolkov (however you spell it)

Agusta Westland

Sikorsky

 

There's probably more but i guess these are the main ones.

[Yurgon]

Hughes/Schweizer

Magdonnel Douglas (MD series)

Bolkov (however you spell it)

Agusta Westland

Sikorsky

 

There's probably more but i guess these are the main ones.

 

Hughes -> MDHC

Schweizer -> Sikorsky

McDonnel Douglas (MDHC/MD series) -> Boeing

 

I guess that's market consolidation. :music_whistling:

 

Bolkov? Doesn't ring a bell here.

 

IIRC Airbus is part of EADS and their civilian helicopter branch is Eurocopter.

 

Let's not forget Mil (Mi-17) and Kamov (Ka-32, Ka-62) who have civilian models in stock.

 

Former helicopter manufacturers include Aerospatiale (discontinued, EADS) and Bölkow/MBB (discontinued, EADS).

 

So that gives an updated list of...

• Agusta Westland
  
• Bell
  
• Boeing
  
• Eurocopter
  
• Kamov
  
• Mil
  
• Robinson
  
• Sikorsky
  

 

But I'm sure there are still important companies missing. Anyone ready to fill in the blanks? :)

[AlphaOneSix]

I think by "Bolkov" he Meant Bolkow/MBB?

 

Also, there is...

 

Kaman SH-2 Seasprite and K-MAX (unmanned version of the K-MAX is in A-stan doing sling loads for the Marines)

 

Columbia Helicopters owns the type certificates now for both the Boeing 107 (CH-46) and 234 (CH-47), and they hope to begin producing them (civilian versions, of course) in the near future. I think they already manufacture parts for them?

 

Erickson Air-Crane owns the type certificate for the Sikorsky S-64 (CH-54 Tarhe) and produces them for civilian work.

 

There is also still MD Helicopters (the "MD" doesn't mean anything) that produces the civilian version of the former McDonnell Douglas helicopters (Boeing only makes the military models, AH-64 and A/MH-6 series).

 

There are tons of other smaller manufacturers, but they are either really small, or are just roundabout subsidiaries of larger companies already mentioned.