AAWSAP DIRD, Space Access: Where We’ve Been and Where We Could Go, March 2010

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One of the difficulties with silicon carbide (SiC) is that it is ridged fibers, like very-small­
diameter rods. When the NASP team visited Japan in 1988, one of the very interesting
products of the UBE Corporation was Tyranno® cloth (see Figure 23). Composed of
strong, flexible fibers from natural Feldspar, Tyranno cloth handled and felt like tweed
cloth. The cloth could be wetted by liquid aluminum or titanium, and the NASP team
saw examples of both aluminum and titanium metal matrix composite (MMC) products.
For example, an aluminum MMC piston and connecting rod was being used in Kawasaki
racing engines. And a powder form of aluminum MMC was being used as a dry pigment
that was fused onto the surface of Kawasaki motorcycle mufflers. The MDC NASP team
foresaw many applications for Tyranno cloth for its NASP aircraft.
Figure 22. This 1988 SEP Bordeaux SiC/SiC Panel
Figure 23. UBE Corporation's Tyranno Cloth. The
Could Sustain Temperatures of up to 3,000 °F.
cloth was used industrially in Japan.
With SEP having subsequently closed, little of this
capability remains.
The FDL-7 and Model 176 configurations
always elicit comments that their sharpness
and the associated high heating rates make
them nonviable concepts. However, that is
not the case. Figure 24 shows a 1-inch­
diameter, sintered-nickel nose tip attached
to a 1,000-psi water tank that sweats
water. The result is a functional sharp,
low-drag nose with a minimum-thickness
entropy boundary layer. 12 This tip was
flight-tested on a hypersonic glider (BGRV
flight in 1966) beginning at about 22,000
feet/second . Today, Aerojet Sacramento's
platelet diffusion-bonding technique would
Figure 24. A Porous Nickel Tip Oozing Water.
make this a much easier task. Some
This test lasted 4,300 seconds before the arc
experimental evidence from the BGRV flight
heater cathode-not the nose tip-failed.
indicates the water vapor film in the
boundary did act to reduce the heat transfer to the body aft of the nose.
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