Assault on Bin Laden: mystery of the downed chopper

[Mr London 24/7]

Not new, our Dear quellish posted and discussed before:

http://www.secretprojects.co.uk/forum/index.php/topic,12597.msg260144.html#msg260144

[LowObservable]

Morning all.

"Among the classified products produced under his Boeing tenure were the stealth helicopters involved in the raid that killed Osama bin Laden, which were based on technology developed for the Boeing-Sikorsky RAH-66 Comanche helicopter the Army had canceled."

http://airforcemag.com/Features/Pages/2019/February%202019/George-K-Muellner-1943-2019.aspx?fbclid=IwAR1LiPAHlWNTRBWZvCff1lzP6zYPJGPTmEZNA8vL7-hVITrEUT2KfDy8bIk

[TomS]

Now, that is interesting, and certainly lends credence to the position that the Bin Laden raid helos were a new design (presumably with parts adapted from the S-70 and possibly other aircraft), rather than being simply Black Hawks with minor modifications.

[Sundog]

Now, that is interesting, and certainly lends credence to the position that the Bin Laden raid helos were a new design (presumably with parts adapted from the S-70 and possibly other aircraft), rather than being simply Black Hawks with minor modifications.

IIRC, the original LHX program also looked at a small utility version, besides just the scout. My guess is they took that work and scaled it up to fit the Blackhawk's mechanical systems, so in a sense, mainly just the airframe was new, in a typical "Skunk works" fashion. Or should I say Phantom Works?

[Flyaway]

Now, that is interesting, and certainly lends credence to the position that the Bin Laden raid helos were a new design (presumably with parts adapted from the S-70 and possibly other aircraft), rather than being simply Black Hawks with minor modifications.

IIRC, the original LHX program also looked at a small utility version, besides just the scout. My guess is they took that work and scaled it up to fit the Blackhawk's mechanical systems, so in a sense, mainly just the airframe was new, in a typical "Skunk works" fashion. Or should I say Phantom Works?

Are you saying it was a Blackhawk under the skin just with a different body?

[marauder2048]

Could they really have achieved meaningful acoustic reductions with such an arrangement?

[LowObservable]

Yes, according to most responsible and authoritative reporting going back to 1987.

[Colonial-Marine]

In my opinion abandoning the light utility variant of the LHX was a big mistake and certainly didn't help save the RAH-66 from the chopping block years later. I'm glad it seems something came from all that work at least.

[LowObservable]

The two versions would have had the same engines and rotor system.

What would have been brought over to the LO Hawk would have been flight controls and blade aerodynamics.

[marauder2048]

Yes, according to most responsible and authoritative reporting going back to 1987.

Despite the absence of available noise reduction options/retrofits
for the S-70/UH-60 family + derivatives (S-76 and S-92)?

With ever tightening noise regulations, you should have seen something by now.
 

[LowObservable]

Not necessarily. LO generally involves compromises and the civil operator may not care enough about noise to accept them.

And then there's the rather obvious point that "quiet" in an urban, civilian environment is not the same as "quiet" when you're trying to get the jump on a twitchy foe in the middle of the night, in a mid-sized town in Pakistan.

[TomS]

Yes, according to most responsible and authoritative reporting going back to 1987.

Despite the absence of available noise reduction options/retrofits
for the S-70/UH-60 family + derivatives (S-76 and S-92)?

With ever tightening noise regulations, you should have seen something by now.

I'm not super familiar with helicopter noise regs, but it looks like the new, more stringent Stage 3 rules only apply to new helicopter types, so there may not be a pressing market for hushkits on existing aircraft. 

Also, the lack of commercial S-70s might be a factor -- there really don't seem to be any true civilian users at all, just military and a few paramilitary or police users. 

[TomcatViP]

And the S-70 is heavier. Built for the military. Heavier, more lift (at eq. representative rpm), more noise. It would be like comparing an armored car with a Prius.

[marauder2048]

And then there's the rather obvious point that "quiet" in an urban, civilian environment is not the same as "quiet" when you're trying to get the jump on a twitchy foe in the middle of the night, in a mid-sized town in Pakistan.

The CRH-60 has no acoustic reductions; is there a third type of "quiet" for CSAR?

[RavenOne]

Yes, according to most responsible and authoritative reporting going back to 1987.

Despite the absence of available noise reduction options/retrofits
for the S-70/UH-60 family + derivatives (S-76 and S-92)?

With ever tightening noise regulations, you should have seen something by now.

I'm not super familiar with helicopter noise regs, but it looks like the new, more stringent Stage 3 rules only apply to new helicopter types, so there may not be a pressing market for hushkits on existing aircraft. 

Also, the lack of commercial S-70s might be a factor -- there really don't seem to be any true civilian users at all, just military and a few paramilitary or police users.

Yes there are a lot of former army UH-60A hitting the commercial marketplace ...in last few years.

And S-70i International Blackhawk entering service with likes of LA County FD, Polish Police etc

Here’s Heliops poster of all commercial UH-60A and S-70i

Cheers