Flaming Pumpkin Seeds

[OM]

I'd be careful about assuiming that aviation reporters have the requisite experience in the aviation field. I don't know what Bill Sweetman's educational background is, per se, but every time he wanders off into the world of black projects, it almost makes me cringe. He never seems to question the technological breakthroughs that would be needed to bring his purported "black projects" to life. If nothing else, my engineering education made me a lot more skeptical about what's possible, even on the "bleeding edge" of research and development. And even the "anonymous sources" often don't see the full picture, or they're spreading false information. We should take nobody's word at face value, even if they're telling us the things we want to hear.

Two words.

LIQUID.
METHANE.

...Yes, but is he ingesting it orally or intravenously?

 

[quellish]

...Yes, but is he ingesting it orally or intravenously?

Just like with thermometers, the only real difference is the taste!

 

[crusader97]

Anyone think that there might be some correlation with the YF-24/MRF-24X and the model/aircraft about 2/3 of the way down this page?
http://www.lazygranch.com/hrcs.htm

 

[quellish]

Anyone think that there might be some correlation with the YF-24/MRF-24X and the model/aircraft about 2/3 of the way down this page?
http://www.lazygranch.com/hrcs.htm

I am pretty sure that is an F-117 minus some parts.

 

[Stargazer]

Same here. An F-117 stripped down and left out for spares.

As for the other pics, they look like a Sukhoi fighter and full-scale mock-ups for various space programs.

 

[Stargazer]

I may have found what that would-be secret aircraft is:

In March 1976, the Skunk Works built a model out of wood, all flat panels, thirty-eight feet long, and painted black. It was hauled to White Sands New Mexico for competition against Northrop's candidate. The Skunk Works model had a lower RCS than the pole it was mounted on so Lockheed built a new pole. In April 1976, Lockheed won the competition and the "Have Blue" program was born.

Source: http://www.f117reunion.org/f117_history.htm

I think the similarity between the two speaks for itself. What do others think?

 

[vulture]

A "possible flaming pumpkinseed" ???

Vulture

 

[Stargazer]

Good grief! The Cheshire Cat can FLY!!!!!!!

 

[vulture]

I see someone here is seeing faces Not known if this patch has anything to do with the above image but funny you should mention cats ???

 

[Matej]

I moved this posts from MRF-24X topic to this topic, because the photo on the posted web was discussed here before (and has nothing to to with the MRF-24X).

Anyone think that there might be some correlation with the YF-24/MRF-24X and the model/aircraft about 2/3 of the way down this page?
http://www.lazygranch.com/hrcs.htm

 

[XP67_Moonbat]

Vulture,

The search engine is your friend, so say we all.

Quick Google search of the NRO, B-12, and SLS 2 and voila! I found your patch, dude:
http://cgi.ebay.com/TITAN-IV-B-12-NRO-2-SLS-DOD-USAF-SATELLITE-SPACE-PATCH_W0QQitemZ280402046864QQcmdZViewItemQQimsxZ20090926?IMSfp=TL090926146002r6229

Blackstar is a good go-to guy on here about mystery patches like that.

 

[vulture]

Chill out there Moonbat. I know where the NRO patch originated. I only posted the patch in response to Stargazer's funny remark about "flying cheshire cats." So chill dude!

 

[XP67_Moonbat]

Hey, just trying to help. You should heed your own advice. Try the decaf, it's good stuff!

 

[vulture]

Thanks XP-67 Moonbat, I'll take your advise. It just gets stressful sometimes; and you're right - decaf is great - probably just what I need right now

 

[XP67_Moonbat]

It's all good man. Hey, I don't know if this will help. It's a link describing a paper on external combustion and high-altitude planes. Unfortunately I don't have the funds to order copy.

http://cat.inist.fr/?aModele=afficheN&cpsidt=3527278

I'll keep looking on Google, maybe I can find an available copy for free download.

Also found an AIAA abstract on external combustion using leading edge fuel-injection.
http://pdf.aiaa.org/preview/CDReadyMHYP06_1276/PV2006_7981.pdf

Also, Leik Myrabo's lightcraft airspike experiments also come to mind. Not quite the same thing as Pumpkinseed. But something that made me think of Dr. Myrabo's work.

Though technically, the lightcraft would fall under Space Projects

 

[vulture]

Also appriciated Moonbat - most helpful. And again, thanks.

 

[vulture]

That RCS pole model (full scale) isn't the F=117A. It is however Have Blue way back in the 1970s - April 1976 I think - the piece of hardware was destroyed years ago - all in the name of security. The image above is more recent and different program photo was taken in 2007, so your timing is way off.

 

[overscan (PaulMM)]

"By all means let's be open-minded, but not so open-minded that our brains drop out" - Richard Dawkins

What do you find unacceptable in the idea that its an F-117?

 

[CFE]

I see someone here is seeing faces Not known if this patch has anything to do with the above image but funny you should mention cats ???

The patch is obviously for an NRO orbital mission, and almost certainly has nothing to do with atmospheric flight.

 

[shockonlip]

...
Also, Leik Myrabo's lightcraft airspike experiments also come to mind. Not quite the same thing as Pumpkinseed. But something that made me think of Dr. Myrabo's work.

Though technically, the lightcraft would fall under Space Projects

Unfortunately Moonbat, the shroud on the lightcraft, qualifies this example
as not external burning. if it had no shroud, it would be external burning.

 

[XP67_Moonbat]

Ah, touche'. True that.

 

[Orionblamblam]

Unfortunately Moonbat, the shroud on the lightcraft, qualifies this example
as not external burning. if it had no shroud, it would be external burning.

There's also the little problem that it's not actually *burning.*

 

[shockonlip]

Unfortunately Moonbat, the shroud on the lightcraft, qualifies this example
as not external burning. if it had no shroud, it would be external burning.

There's also the little problem that it's not actually *burning.*

Actually, the point here is the existence of the shroud or cowl.
Whether it is deflagration or detonation, was not the point.

 

[Orionblamblam]

There's also the little problem that it's not actually *burning.*

Actually, the point here is the existence of the shroud or cowl.
Whether it is deflagration or detonation, was not the point.

It's not *combusting.* Thus no burning.

 

[shockonlip]

There's also the little problem that it's not actually *burning.*

Actually, the point here is the existence of the shroud or cowl.
Whether it is deflagration or detonation, was not the point.

OK, so everyone benefits from two points of view!

Scott says that it isn't external burning because it may not be
really burning or deflagrating. So if it isn't burning, it isn't burning
externally then either.

Larry on the other hand doesn't care (in this case), specifically, how
energy or heat or enthalpy is being added. He is pointing out that there
is a shroud around the vehicle that is used to channel the compressed
air from the forebody, like in a NON EXTERNAL BURNING VERSION of a
ramjet or scramjet. And that there is energy addition going on inside
that shroud or cowl for at least part of the flight. And he would not be
surprised if forms of this engine actually did burning in Scott's sense
of the word, like with onboard H2 as fuel.

I think that's really it.

 

[shockonlip]

I have a problem with other aspects of the "Flaming Pumpkin Seed"
besides its external burning.

Look at the turbojet inlets. What do you see?

NACA Inlets !!

As I understand these, they are not good for supersonic flight.
Maybe OK for small aux intakes, but not the main turbojet intake.
In fact, so says my copy of Seddon and Goldsmith.

 

[airrocket]

That is a way cool concept vehicle... got to luv it.
External compression (shock confined combustion) was studied and demonstrated in depth by Dugger of JHU/APL in 1956 and RAE in 1966 (boundry layer diverter ahead of the wedge crest and a step at the wedge crest) at M10 conditions. ISP ....heated gasified hydrogen from skin cooling (energy recovery) reached ISP of 5,000 out of the nozzle (doublewedge with discret hole and wall slot injectors) prior to combustion. External compression can also be utilized to replace aerodynamic control surfaces (negative trim drag) flaps, elevators, ailerons, rudder etc...

 

[airrocket]

1,000 ISP was axial force. 5,000 ISP at M7-M10 from injectors alone.

 

[airrocket]

Appears the NACA inlets support a subsonic or low supersonic take-off,loiter, landing jet propulsion phase. The vehicle concept appears credible to me. The shock confined injectors are located around the perimeter at the apex or widest sharp central diamond edge.

 

[shockonlip]

That is a way cool concept vehicle... got to luv it.
External compression (shock confined combustion) was studied and demonstrated in depth by Dugger of JHU/APL in 1956 and RAE in 1966 (boundry layer diverter ahead of the wedge crest and a step at the wedge crest) at M10 conditions. ISP ....heated gasified hydrogen from skin cooling (energy recovery) reached ISP of 5,000 out of the nozzle (doublewedge with discret hole and wall slot injectors) prior to combustion. External compression can also be utilized to replace aerodynamic control surfaces (negative trim drag) flaps, elevators, ailerons, rudder etc...

Agreed on way cool concept ... got to luv it - Agreed!
I think we are of like mind on hypersonic concepts - let's publish them all - and do more!
And lets actually built em and fly em!

Anyway, I am unaware of Dugger's 1956 in depth study.
I have a copy of his 1958-1961 in depth study, on ERJ (External Burning Ramjet),
EEJ (External Expansion Ramjet), and HRJ (Hypersonic Ramjet). In fact, I believe
the HRJ work led to Billig's first successful scramjet engine which was external burning
initially, but which later was converted to a cowled design.

ERJ conclusion was that it was good for cruise. In fact it could produce net thrust,
and increase airfoil lift up to 2X-3X (note - airfoil lift - think of neat possible shapes!),
greatest propulsive efficiency was with slender shapes, fuel specific impulse for cruise,
at moderate hypersonic speed, was between rockets and conventional ramjets. At higher
Mach, fuel specific impulse was better that conventional ramjet (CRJ) (but remember
CRJ is subsonic burning and at higher mach, that doesn't work so well), and ERJ is actually
supersonic burning.

However ERJ as a primary powerplant is much poorer for missions requiring acceleration.

Dugger indicated that more work needs to be done on optimizing the fuel distribution and
or using favorable pressure field interference effects.

But HRJ, what we know today as scramjet, is actually better than CRJ or ERJ.

So the point is that why would you do ERJ, except for cruise optimization or control
(as you mentioned). Unless someone had made ERJ better, which we haven't seen really
any work on that I know of, as people seem to be focusing on HRJ or scramjet.

Do you have a ref. for the RAE 1966 work?

Thanks,

Larry

 

[shockonlip]

Appears the NACA inlets support a subsonic or low supersonic take-off,loiter, landing jet propulsion phase. The vehicle concept appears credible to me. The shock confined injectors are located around the perimeter at the apex or widest sharp central diamond edge.

Hi again.

So where are NACA inlets used for low supersonic?
I don't recall ever seeing one used for that, at least on an aircraft.
On a missile? Still struggling to remember one.
Seddon and Goldsmith indicate low subsonic.
The NACA inlet actually has a downward ramp into the inlet, which
at supersonic will be seen as flow expansion, and cause a flow acceleration
such that inlet must be sized for that instead of normal capture. And the
normal vortex flow at subsonic will cause more shocks, for more wave drag.

Regards.

 

[Orionblamblam]

So where are NACA inlets used for low supersonic?
I don't recall ever seeing one used for that, at least on an aircraft.

 

[elmayerle]

Let us not forget that a lot of cooling air scoops on low-supersonic aircraft still use NACA inlets.

 

[Machdiamond]

The French Microjet also used NACA inlets for its two TRS-18, but that does not mean it was a good idea - especially right above the wing in its low pressure area (in the what were they thinking department).

http://www.machdiamonds.com/microjet.html

--Luc

 

[Sundog]

So where are NACA inlets used for low supersonic?
I don't recall ever seeing one used for that, at least on an aircraft.

That was a test and they were changed to pitot inlets because they didn't work so well. I don't recall if it was due to lack of pressure recovery or due to flow distortion or some combination of both.

 

[Stargazer]

Here are the two F-93s after their lease to NASA.

Aircraft #2 still has the NACA inlets, while #1 has already been fitted with pitot intakes.
I think both ended up being thus modified.

 

[shockonlip]

Thanks gents for the F-93 posts !

So thus my quandry on this concept, as cool as it is.

Main inlet is probably not good for what it is supposed to do.

Per Dugger's study, external burning is cool for cruise. Vehicle
is not actually what I'd call slender, but it could be made that way.
I wouldn't expect acceleration capability from the external
burning, unless improvements have been made there, per Dugger.

But it is a concept, so in that light, it is a cool design and
perhaps a starting point to fix it's problems we discovered.

And you never know, if you think it's real, perhaps the correct
stuff wasn't seen. But as the security dudes would say, given
its state, it's plausible to deny it.

This all of course is my current opinion.

 

[flateric]

Looks much like of one of full-scale F-22 RCS models known, representing aircraft rear fuselage with TVC nozzles and horizontal tail with fuselage chopped and streamlined along lines of tail leading edges in plan view. Had photo somewhere, but can't check it right now.

May be wrong about this as well.

 

[Steve Pace]

Here are the two F-93s after their lease to NASA.

Aircraft #2 still has the NACA inlets, while #1 has already been fitted with pitot intakes.
I think both ended up being thus modified.

Could you possibly send high res of these three images to me?... Thanks! BTW: The bottom picture I've seen in color somewhere.

 

[Jeb]

"By all means let's be open-minded, but not so open-minded that our brains drop out" - Richard Dawkins

What do you find unacceptable in the idea that its an F-117?

Nose/canopy/forebody lines are off. The canopy is set further back from the nose than an F-117 would be and the nose is more horizontal.