From: skunk-works-digest-owner@harbor.ecn.purdue.edu To: skunk-works-digest@harbor.ecn.purdue.edu Subject: Skunk Works Digest V3 #56 Reply-To: skunk-works-digest@harbor.ecn.purdue.edu Errors-To: skunk-works-digest-owner@harbor.ecn.purdue.edu Precedence: bulk Skunk Works Digest Thursday, 10 June 1993 Volume 03 : Number 056 In this issue: Falling objects and shields please add me Re: Falling objects and shields Re: Falling objects and shields Re: Falling objects and shields Powered vertical landings 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: S.Dray@ste0402.wins.icl.co.uk Date: Wed, 9 Jun 1993 10:43:32 +0100 Subject: Falling objects and shields - ------------------------------ Start of body part 1 - ------------------------------ Start of body part 2 An English Magazine called focus carried an article on a new reusable re-entry vehicle recently. Could this be the the vehicle that was being discussed with the mention small and heat shields unfortunatly i dont have the document to hand. The vehicle is called DC-X Delta Clipper and is being built by Mcdonald Douglas. The prototype will fly no higher the 6,700 M and is being used for testing Nav equipment and software. The ideas is that a payload can be delivered into orbit for less that a #1000 per Kilo (Cheap Huh BY BY Shuttle) When DC reaches orbit the payload is delivered by means of a simple spring mechanism. The good thing is the payload pallets will be standard. That was a very short resume of the article which goes on for couple of pages with pictures. By the way this thing comes down on its jets a bit like real SC-FI rockets landing Sonic Booms and flames as well. - ------------------------------ End of body part 2 ------------------------------ From: "FLDD01::M243775" Date: 9 Jun 93 07:54:00 CST Subject: please add me Please add me to the list. They tell me my address is: m243775%fldd01.decnet@mdcgwy.mdc.com Thanks! Brett A. Hoffstadt ------------------------------ From: tom@gordian.com (Tom Ambrose) Date: Wed, 09 Jun 93 08:43:05 PDT Subject: Re: Falling objects and shields The Delta Clipper has been been undergoing engine tests out at White Sands over the past month or so. The first test flight is slated for July. I believe there are going to be three main test flights. Each flight will reach a higher altitude and try more mobility of the vehicle. The past 2 or 3 AW&ST have had articles on DC-X. I know some people that are working on the program. We were discussing the landing method. I think it would be much cheaper (and easier) to just deploy a parachute for the final decent. The powered, nose up, vertical landing requires pretty fancy software and control systems. I have often given them a hard time calling the project "the lawn dart" because I told them I thought it would land that way. - -tom ------------------------------ From: Brent L. Bates ViGYAN AAD/TAB Date: Wed, 9 Jun 93 12:33:21 EDT Subject: Re: Falling objects and shields I don't like rocket powered landings either. They are usually EXTREMELY high G landings and I wouldn't like getting squashed like a bug under those kind of G's. Brent L. Bates Phone:(804) 864-2854 M.S. 361 FAX:(804) 864-8469 NASA Langley Research Center Hampton, Virginia 23681-0001 E-mail: blbates@aero36.larc.nasa.gov or B.L.BATES@larc.nasa.gov ------------------------------ From: larry@ichips.intel.com Date: Wed, 9 Jun 1993 13:20:21 -0700 Subject: Re: Falling objects and shields Tom Ambrose writes: > ... >I know some people that are working on the (DC-X) program. We were discussing the >landing method. I think it would be much cheaper (and easier) to just deploy a >parachute for the final decent. > > The powered, nose up, vertical landing requires >pretty fancy software and control systems. I don't doubt that would be simpler. But after scale-up (DC-Y) we're going to need to test powered landing anyway. The whole goal of DC-X is to be a demonstrator of as much of the DC-Y orbital mission as possible. In my opinion, this necessitates the powered landing demonstrations. The question I have is, since DC-X won't be demonstrating orbital mass fraction, is the industry comfortable with DC-Y being SSTO feasable? Brent L. Bates writes: > I don't like rocket powered landings either. They are usually EXTREMELY >high G landings and I wouldn't like getting squashed like a bug under those >kind of G's. I like the powered landing but am unfamiliar with the any parameter profiles during descent. My thoughts are that any abort phase would need powered landing anyway, and one would expect to have a lower G load in that case. I predict that someday we will have airbreathing engines for this or a similar bird, and probably even a higher L/D, that will allow more control over normal terminal phase G loads. No I like the vertical powered landing and what it is capable of providing in the way of flexibility and safety. I think it's time we start developing these new approaches. I also don't think that DC-X/Y should negatively impact any hypersonic airbreathing initiatives. We need to do both. Larry ------------------------------ From: Indiana Joe Date: Wed, 9 Jun 1993 18:25:42 -0400 (EDT) Subject: Powered vertical landings Tom Ambrose writes: > ... >I know some people that are working on the (DC-X) program. We were >discussing the landing method. I think it would be much cheaper (and easier) >to just deploy a parachute for the final decent. However, for most bodies in the solar system, you don't have an atmosphere. Powered vertical landings will be essential for flights that don't end on Earth. >The powered, nose up, vertical landing requires >pretty fancy software and control systems. Nothing we haven't done before with Apollo, I think. >... ================================================================================ "Indiana" Joe Claffey = Disclaimer: All non-quoted opinions CLAFFEY_JOR@CCSU.CTSTATEU.EDU = expressed are my own, and anyone else Quote: "Make no small plans." = trying to take credit for them is in - Daniel Burnham = big trouble! ================================================================================ ------------------------------ End of Skunk Works Digest V3 #56 ******************************** To subscribe to skunk-works-digest, send the command: subscribe skunk-works-digest in the body of a message to "listserv@harbor.ecn.purdue.edu". 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