"Guy Alcala" wrote in message
. ..
Kevin Brooks wrote:

"Peter Kemp" wrote in message
...
On Sun, 21 Mar 2004 23:07:41 -0500, "Kevin Brooks"
wrote:


"Peter Kemp" wrote in message
.. .
IMO the only significant difference between the, for the VVIP role
is
that the EH101 has a hell of a lot more hours under it's elt and is
rather more proven.

The S-92 is a growth model of a proven design that is already in use
by
HMX-1, and I doubt its flightworthiness is of issue.

The commonality of the S-92 with the H-60 appears to be greatly
exaggerated. It
may have started out that way, but the numerous changes since have really
made
it a new helo with some concepts borrowed from the H-60. However, by the
time
they could get into service, I imagine the commercial users will have put
enough
hours on it to eliminate any major worries in that area. But Sikorsky's
just
making the first commercial delivery now, so ordering anytime soon would
still
be taking a bit of a risk.

I am not sure how much risk you are talking about; Sikorsky is ballyhooing
the fact that the S-92 is the first and only helo to have so far been
certified under the FAA Part 29 requirements. It has been flying since 1998,
apparently without major mishap, a total of five prototypes logging hours
(about 2500 to date) over the years since then. The critter even won the
Collier Trophy year before last. They already have over 20 firm sales, some
seventeen options, and a handfull of others have made deposits towards
future purchase. based upon all of that, this appears to be a pretty
low-risk program. As to commonality with the S-70/UH-60 family, it shares
the same rotor system as the UH-60M (albeit the latter has blades a foot
shorter); as one source noted, the "engines and dynamic components are
basically those of the Blackhawk family".


snip

Checking JAWA today it looks like they have a virtually identical
cruise speed, but the EH101 has a 50% greater load and between 20% and
150% more range (not much in the way of comparable data). For a SF
mission or CSAR where armour and navair and weapons are likely to be
added I'd say that's a significant difference.

Hard to say, as you noted the data comparisons right now are kind of
sketchy. I don't see the load factor as being critical in the CSAR role
(and
as of now that is the projected mission--USAF is committed to the CV-22
for
the SOF insertion/extraction role), and I doubt the "150%" range factor.
Where it apparently *does* have a distinct advantage is high/hot
operations.

snip

AvLeak mantioned a month or two ago that the proposed "VH-92" was being
given a
power boost to bring its hot/high performance into line with the "US-101."
I
don't remember the details (it was a more powerful version of the CT-7),
but the
Sikorsky person they were talking to may have said it would exceed the
US-101's
hot/high performance.

Very possible. From what I have read the S-92, while being certified at
lower payload capacity than the EH-101, has actually flown (in and out of
ground effect) at about the same maximum gross weight as the EH-101
advertises.

Brooks


Guy