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Comment by nostrademons | Hacker News Reader

This seems a lot like buying a Mig-21. Yes, you can get them for dirt cheap (under $50K in the Mig-21's case [1]). But the cost in parts, maintenance, fuel, and hiring an instructor pilot so you don't kill yourself the first time you take it up will quickly exceed the initial purchase price. There's a reason why people are selling them.

[1] http://www.city-data.com/forum/automotive/503914-mig-21-ebay...

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The difference with helicopters is that unlike the MiG-21, there's significant commercial demand for their use (it just happens to be in a bit of a trough at the moment) and most of the costs are proportionate to how many flying hours it gets - they don't have the sharp year on year depreciation associated with commercial fixed wing aircraft because innovation is slower, design lives are longer and required maintenance intervals generally aren't measured in years. Historically, helicopters have even been known to appreciate in value over several year economic cycles.

If I wanted to make money, I'd much rather have one AW109A than 4 Mig 21s.

> Required maintenance intervals generally aren't measured in years

Isn't that a bit misleading? There are components and systems that only need servicing every few years, but general practice with helicopters is phased inspections every m months (the military generally does every 6 months).

Sure, helicopters are easier to work on and generally require less maintenance per flight hour than jets do, but they're still aircraft, so they're greedy and needy.

My experience in the military was that phased inspections on fighter aircraft was done every N flight hours, not based on a fixed amount of time, I would assume helicopters are the same, but I was under the impression that helicopters required more maintenance, not less, due to the increased mechanical complexity, but I never got to work on those, so I really have no idea.

Huh. When I was an engineer (civilian) working on helicopters at a test squadron (HX-21), they put their aircraft in phase every 180 days, flight hours or no. But I guess the key words are "test squadron".

The rotor hub, transmission, and tail rotor are mechanically complex, but there are fighter aircraft out there with way more mechanically complex systems (F-35B lift system comes to mind).

It could be that it has a special, experimental, or provisional airworthiness certificate, in which case that certification determines inspections rather than FARs. If it had none of those, and wasn't an aircraft used for hire, then the annual inspection applies. And all that means is that the requirements for an annual inspection are met within the previous 12 calendar months, so they could certainly do 1/2 the required annual inspection every 180 days.

You may be right. I am not at all knowledgeable about airworthness certificates. I did assist with supplying engineering documentation for flight clearances, but those are not the same thing.

The military pretty much follows FARs, and where they don't, they're more strict. I'd expect the military does either 100 hour or progressive inspections, hour defined as "time in service" which for most aircraft is flight time as measured by a landing gear squat switch. Many general aviation aircraft will use tachometer time where they don't have such an flight time meter. Progressive inspections pretty much are 100 hour inspections but get broken down to e.g. 4 inspections every 25 hours, and the 100 hour inspection is only considered complete once the last inspection for that cycle is done. But they could do 10 inspections every 10 hours, or whatever.

I'm thinking less of the periodic inspections which aren't that expensive in the scheme of aircraft ownership costs, and more of the fact your average commercial jet needs heavy checks which essentially rebuild the aircraft every six years at a multimillion dollar cost even if it hasn't been heavily used. afaik the mandatory time-scheduled heavy maintenance on most helicopter types is comparatively limited and it's replacing components - according to flying hours rather than age - that costs virtually all the money.

Out of curiosity, what does the average person need a helicopter for? The expertise and cost is no joke.

Enclosed autogyros and weightshift ultralight airplanes should should suffice for what its worth. And they are presumeably safer to fly!

https://en.wikipedia.org/wiki/AutoGyro_Calidus

https://www.youtube.com/watch?v=8OU98We-mcw

If you do need a heli, you are hardly an average person, are you?

And aren't helis mostly used when you specifically need the ability to land on a building or hover?

In general, yes, but there's a fairly large market for filming with helis since you can mount nice camera equipment unrestricted by fixed wing fuselages, propellers, etc. and take nice, slow shots at low altitude. Of course, this is being replaced by much cheaper drones. Sightseeing is another decent size use case, which often doesn't really involve hovering. And news/traffic reporting usually occupies a few helis in cities where they're primarily cruising around.

They sounds awesome fun for one thing... If cost was no object, I'd certainly be roaming the skies in one, rather than rollerblading and such... (I mean, I'd do both, not at the same time probably)

I'm trying to imagine operating a helicopter with rollerblades on.

Reminds me of reading how one of the Solyent founders bought a genome sequencer at auction. May well have been cheap, but you need a lot of knowledge and materials to use one, and the tech is evolving pretty rapidly, so will probably be outdated pretty soon.

Don't forget that this (and every spare part) classifies as military hardware which has severe limitation of export/import.

Not everything military is necessarily ITAR'd. A lot of components for legacy aircraft are now far outclassed by COTS equipment, or are now COTS equipment themselves, so there's not a need for especially stringent export/import requirements anymore. So these components might be removed from ITAR (Defense/State Department) control, and shifted to being controlled by the EAR (Export Administration Regulation) and the US Department of Commerce, which is less restrictive.

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