From: To: Subject: Skunk Works Digest V5 #144 Reply-To: Errors-To: Precedence: bulk Skunk Works Digest Sunday, 24 July 1994 Volume 05 : Number 144 In this issue: Re: Skunk Works Digest V5 #143 (Fwd) Air-launched Black Horse (fwd) See the end of the digest for information on subscribing to the skunk-works or skunk-works-digest mailing lists and on how to retrieve back issues. ---------------------------------------------------------------------- From: "Thomas A. Gauldin" Date: Sat, 23 Jul 1994 11:03:47 -0400 (EDT) Subject: Re: Skunk Works Digest V5 #143 Seeing the comments about the T' Birds being in Dayton reminds me of a show they did at Pope AFB about 3-4 years ago. I saw what I considered the most impressive thing an airplane ever did, but now nobody even believes me when I tell them what I saw. During the show, one of the planes made a low, very slow approach to the runway with the gear retracted. It then pitched up at the end of the runway and applied just enough power to maintain about 20 feet of height while balancing on the thrust of the engine alone. The plane slowly continued to balance alone on thrust down the entire length of the runway and then increased thrust to make a vertical ascent. I assume to this day that the plane did not have vectored thrust, so I cannot explain how the pilot maintianed control. The low speed and high high pitch angle surely preculede aerodynamic control. If any of you folks going to Dayton see the maneuver again, take a minute and tell me how they maintian control. Actually, I'd just be happy to know that I wasnt' just imagining the maneuver . Thomas A. Gauldin Here's to the land of the longleaf pine, Raleigh, NC The summerland where the sun doth shine, BSRB45A on Prodigy Where the weak grow strong and the strong grow great, FAX (919) 676-1404 Here's to Downhome, the Old North State. ------------------------------ From: Frank Markus Date: Sat, 23 Jul 1994 15:39:56 -0400 Subject: (Fwd) Air-launched Black Horse (fwd) Forwarding message by MLINDROOS@FINABO.ABO.FI - -------------------- From: MLINDROOS@FINABO.ABO.FI (Marcus Lindroos INF) Subject: Air-launched Black Horse (fwd) Date: Tue, 19 Jul 1994 15:20:15 GMT Organization: ABO AKADEMI UNIVERSITY, FINLAND (Forwarded from Mitch Burnside Clapp) - ----------------------------------------------------------------- - -------- There are five good reasons to reject the notion of launching Black Horse from another vehicle altogether. First, it's dangerous. You have to make two aircraft fly well when joined, be able to separate safely, and still fly well after the separation. There is no way to build up in flight test to a separation; you either go for the whole thing or you don't try it. It is possible to accept this level of risk, but doing so makes it less attractive and much more expensive. Second, we have limited experience with aircraft-aircraft separations. In aviation history, we've done maybe 400 of them. We did more refueling than that every shift during Desert Storm. There is no complexity assiciated with in-flight propellant transfer - -- it is as easy and as routine as instrument landing. Third, aircraft- aircraft separation reduces the altitude for separation over inflight propellant transfer. All other things being equal, the ensemble is under the thrust of only one aircraft's engines and under the drag of both aircraft, plus the interference drag between them. Fourth, a new facility, perhaps a crane, will be needed to mate and demate the ensemble, which limits basing flexibilty. Finally, the carrier aircraft requirements are much more difficult than for a tanker. It needs to bear not only the weight of the propellant for orbit, but also the dry weight of the orbiter, and its payload, and the mating and separation hardware. This dwarfs the weight of the refueling system. For this reason, you have to develop an entirely new aircraft, or make major, airworthiness-affecting structural modifications to an existing aircraft. Tanking is safer, more familiar, better performing, more flexible, and cheaper than aircraft-aircraft separation. This is particularly true for the Ukrainian An-225. There's only one of them, and there will only be one because the tooling is gone. It has no range to speak of, and poor time to climb performance. I would rather tank from three KC-135s in sequence than use an An-225. Doing an international aircraft modification program is probably too much trouble and offers no obvious benefit to justify the costs and risks involved. The only advantage to aircraft-aircraft separation is the ability to eliminate the crew. I'm personally not in favor of that. Putting a crew on an existing spacecraft is expensive because existing spacecraft are dangerous. "Man-Rating", as NASA understands it, is essentially the process of making artillery safe to fly. An aircraft has inherently safe abort modes, and if it ever gets really bad, you can eject. Even failing that, you can always dump fuel and fly back to any airstrip. This secure intact abort requirement is why aircraft are man, woman, and child-rated from the start. Truly useful spacecraft will share the same features, and the simple truth is that we know how to do that with aircraft already. Put the crew in pressure suits (routine) and let them fly the jet (also routine) and there's nothing that is really any different from high perofrmance aircraft today except for the reentry. Besides, don't you want to fly it? - ----------------------------------------------------------------- - -------- (Regarding Black Horse and future development, Mitch says ARPA will contribute some money for now. What happens after that, nobody knows. Let's keep our fingers crossed!) MARCU$ ------------------------------ End of Skunk Works Digest V5 #144 ********************************* To subscribe to skunk-works-digest, send the command: subscribe skunk-works-digest in the body of a message to "". If you want to subscribe something other than the account the mail is coming from, such as a local redistribution list, then append that address to the "subscribe" command; for example, to subscribe "local-skunk-works": subscribe skunk-works-digest To unsubscribe, send mail to the same address, with the command: unsubscribe skunk-works-digest in the body. 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