The Flame Barrier in 1955

OK, I'm too lazy/disinterested to look this up.
With that in mind, what is the "flame/heat barrier"?

Not expecting an answer, but thanks anyway,
Dale

Dale Carlson wrote:
OK, I'm too lazy/disinterested to look this up.
With that in mind, what is the "flame/heat barrier"?

Aerodynamic heating. That is, how fast can you go before your airframe
melts? And can you use appropriate shapes and materials to extend that
limit?

--
Dave Michelson

Matt wrote:

Yeah, but it was the fastest LOOKING plane ever built, even beating
the NF-104A on that score.


It reminds me of Ernst Udet's remark on first seeing the He-176 rocket
plane: "Those aren't wings, those are running boards!".
Except for unintentionally discovering roll-coupling, it was considered
the biggest flop of the X-planes that actually got built.
Sure looked great though.

Pat

wrote:

This is a new idea. What are lenticular ramjets? I have photos of
the X-3 with ramjet tubes on the wingtips, but nothing lenticular.


The lenticular ramjet was to be mounted inside of the wing with the
whole leading edge incorporating an inlet along its length, combustion
occurring inside the wing structure, and the trailing edge forming the
exhaust.
The Hermes II test missile's upper stage incorporated lenticular ramjets
in its wings http://www.designation-systems.net/d.../ssm-a-16.html
http://www.designation-systems.net/d...v-a-6(ram).jpg
Oddly, if you look at the wing design on the Pan-Am Space Clipper from
"2001", it looks like it may have lenticular ramjets incorporated in it
also, feeding from multiple inlets on its leading edge that exhausted
over the rear top surface of the wing.

Pat

Dale Carlson wrote:
OK, I'm too lazy/disinterested to look this up.
With that in mind, what is the "flame/heat barrier"?

Not expecting an answer, but thanks anyway,


Aerodynamic heating that occurs at multi-Mach velocities.
This was a big bugaboo in the 1950's, when aircraft were pretty much all
built out of aluminum and magnesium alloys, but the article does talk
about titanium being able to deal with the heat, and the X-15 showed
that nickel alloys could also be very useful in this regard in the years
after the article was written.

Pat

On May 21, 5:09 pm, Pat Flannery wrote:

The lenticular ramjet was to be mounted inside of the wing with the
whole leading edge incorporating an inlet along its length, combustion
occurring inside the wing structure, and the trailing edge forming the
exhaust.

Never heard of it. I think. Wasn't there an idea about an externally-
ignited ramjet?

The Hermes II test missile's upper stage incorporated lenticular ramjets
in its wings
http://www.designation-systems.net/d...v-a-6(ram).jpg

Thanks. In my wanderings through old NASA papers, I've seen that
shape -- the big wing and cruciform tail -- in some drawings, but I
never paid any attention to any of that.

Oddly, if you look at the wing design on the Pan-Am Space Clipper from
"2001", it looks like it may have lenticular ramjets incorporated in it
also, feeding from multiple inlets on its leading edge that exhausted
over the rear top surface of the wing.

I noticed that "step" in the Space Clipper wing when I built the
model. I never thought it might be anything more than a quirk of the
Aurora kit, or at most maybe just a simple wing.


Mike

wrote:
I noticed that "step" in the Space Clipper wing when I built the
model. I never thought it might be anything more than a quirk of the
Aurora kit, or at most maybe just a simple wing.


What hit me as odd were the holes in the leading edge of the wing;
that's something downright strange.
One of the preproduction drawings of the Orion class space clipper shows
everything aft of the thick section of the forward wing (rocket engines,
etc.) separating for some reason, though I don't know why.
The X-3 minus the jets and their space and weight replaced by the twin
XLR-11 rocket engines would have looked even more sleek than the
original version,and with the wingtip ramjets on it should have allowed
it to hit around Mach 3 from a surface liftoff...at least for a short
period of time.
But the combo of low powered jet engines, lack of area ruling on the
fuselage to cut drag as it went from subsonic to supersonic flight, and
the fairly basic intake design that didn't deal well with the supersonic
boundary layer pretty much doomed it from the get-go.
You want to imagine something really sleek, picture the built fuselage
design with area ruling incorporated into it over the wings, and the two
XLR-11s in the tail...with no air intakes.
It would have looked like a finned needle going through the air.
Although it looked incredibly streamlined from above and the side, seen
head-on the X-3 had a lot of wetted area...like trying to drive a very
pointed square peg into a round supersonic shockwave hole:
http://www.globalsecurity.org/milita.../X-3_3view.gif
The view for the pilot as he came in to land must have been very limited
and scary indeed, particularly given the fact that the very high stall
speed would mean a considerable nose-up attitude during the last few
seconds before touchdown...both to maintain lift and cut touchdown speed.
This aircraft really needed a big extensible belly periscope for
landing; it had one of the most limited views for the pilot outside of
the XF-103 design, and that one did grow a periscope as the design
advanced, although it was to be atop the fuselage.


Pat