Thanks Sferrin.
Canceled during the Clinton Administration. Nice cartoon....I wonder if it could have been made to work. It also makes you wonder if the complete tilt toward stealth is worth the squeeze.
Canceled during the Clinton Administration. Nice cartoon....I wonder if it could have been made to work. It also makes you wonder if the complete tilt toward stealth is worth the squeeze.
Considering that it appears the X-51 was a failure, I'm guessing if it had made it past concept stage one of two things would have happened.
ReplyDelete1) It would have been cancelled due to budget overflow
2) The reqs would be scaled back to accommodate a Mach 3 or 4 missile instead.
This design was unrelated to X-51. It was suppose to be ramjet powered not scramjet powered.
ReplyDelete"HyStrike will begin the development of an operational hypersonic weapon that will be fielded in the 2005 to 2012 time frame. A Low-Cost Missile with reduced radar cross-section is to be demonstrated by the US Navy. The surface-launched system could hit underground targets to a depth of 12 meters after flying at beyond Mach 4. The wingless missile would change direction in flight by using a bending body joint. The LCMS concept comprises a fin-less, bending body airframe, fixed geometry annular inlet, and a slip-out booster/ramjet engine. It demonstrates through a series of ground and flight tests the technologies required to deliver a 700-pound payload to a range exceeding 700 nautical miles at a speed of Mach 4.0.
The Office of Naval Research sponsors the Hypersonics Weapons Technology (HWT) and the Low-Cost Missile (LCM) programs. The HWT Program is investigating technologies necessary for effective weapon-system operation in the hypersonic realm. The LCM Program - commonly known as Fast Hawk - is developing an entry-level capability for a Mach 4 hypersonic weapon. Both of these ONR programs will feed into the Hypersonic Strike (HyStrike) Program sponsored by the chief of naval operations (N88; N87; and N86)."
The HWT -following several name changes- eventually became the X-51. Fasthawk was the cancelled LCM. I think they fell victim to the "better is the enemy of good enough" problem. Wanted to go right to hypersonics and when that failed they were left with nothing.
"better is the enemy of good enough"
DeleteThanks that articulates the way I feel about a lot of things and attitudes both related and unrelated to military programs. Who said it? I had been repeating " A good plan today is better than a perfect plan tomorrow" but your quote is better.
@sferrin
DeleteI'm sure they are unrelated, but that doesn't change anything. I also don't believe the engine type had anything to do with the X-51's failure and does not give any guarantee the missile would work.
The quote you've pasted actually proves my original statement, not refute it. It talks about how they're demonstrators can only go to Mach 4; even the Blackbird could hit Mach 4.
1. The LCM (Fasthawk) was designed for Mach 4 and used a ramjet. HWT (which became the X-51) was to be hypersonic and use scramjets. Two different programs altogether. From my post above:
Delete"The Office of Naval Research sponsors the Hypersonics Weapons Technology (HWT) and the Low-Cost Missile (LCM) programs. The HWT Program is investigating technologies necessary for effective weapon-system operation in the hypersonic realm. The LCM Program - commonly known as Fast Hawk - is developing an entry-level capability for a Mach 4 hypersonic weapon."
2. No Blackbird could do Mach 4.
The "official" speed record for the Blackbird was Mach 3.3. I can promise you it went faster flying over Russia and China. Probably much faster.
ReplyDeleteSource? The fastest I've ever seen attributed to any variant in actual *reliable* print was Mach 3.6 in one of the earlier test flights of the A-12. Do have any evidence (aside from your assurances) that a Blackbird reached Mach 4? And the "actual" official speed record is a stretch on one of the airframe's last flights on the way to a museum of 2,242 mph or Mach 3.4.
DeleteFrom a retired Blackbird flight test engineer (when they were at Dryden:
Delete"On Sun, 30 Nov 2003 06:06:38 GMT, Scott Ferrin
wrote:
> On Sat, 29 Nov 2003 19:54:46 -0800, Mary Shafer
> wrote:
> >If you go faster than Mach 3.5 the bow shock off the nose will impinge
> >on the leading edge of the outboard section of the wing and melt it
> >off if you do it for very long. It's OK for a dash, but not for
> >cruise. That's pretty solid science.
>
> You know out of all the "how fast will it REALLY go" discussions
> that's the first time I've heard an answer that satisfied me. Many
> here are familiar with that X-15 that burned off it's ventral fin from
> shock inpingment from that test ramjet.
Those who aren't can see the photos in the paper on the difference
between actual and flight hypersonic aerothermodynamics by Iliff and
Shafer in the technical archive at www.dfrc.nasa.gov. Or, if you have
access to the newest book about the X-15, "Hypersonic", by Dennis
Jenkins and Tony Landis, you can see it there. This is a great book,
with wonderful photos, many of which haven't been published before. I
really recommend it, just as I recommend Dennis's book on the Space
Shuttle. Buy them both or put them on your holiday gift list if
you're at all interested in the X-15 or the Shuttle.
> Most of the answers I'd
> heard in the past for why it can't go a lot faster than 3.2 is
> "because it can't". The shock thing makes total sense.
And you can work it out yourself with an accurate drawing of the
airplane and a protractor. It takes a tiny bit of compressible flow
knowledge, but not much.
> I'd read that
> one of the A-12s hit 3.6 at 97,600 which is probably close to the
> alltime best. It's definitely the best I've ever seen published.
I don't think this is right, though. I've heard both 3.5+ and
97,000+, but not at the same time. That's because the altitude was
attained in a "zoom" climb (remembering that the SR-71 zooms fairly
gently). I think that this record is discussed in "Blackbird Rising",
the book about the Cat I/II testing.
I know the guy who set the Mach record, by the way. He confirmed it
to me as being in a dash, not cruise, and said they were timing the
dash very carefully. Pilots are kind of fussy about melting holes in
the wings.
Mary
--
Mary Shafer Retired aerospace research engineer