From: skunk-works-digest-owner@harbor.ecn.purdue.edu To: skunk-works-digest@harbor.ecn.purdue.edu Subject: Skunk Works Digest V3 #43 Reply-To: skunk-works-digest@harbor.ecn.purdue.edu Errors-To: skunk-works-digest-owner@harbor.ecn.purdue.edu Precedence: bulk Skunk Works Digest Sunday, 16 May 1993 Volume 03 : Number 043 In this issue: Re: Waveriders in P/M Grob Strato 2C Sea Shadow in LA Times 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: "Charles A. Lind" Date: Sat, 15 May 1993 07:55:30 -0400 (EDT) Subject: Re: Waveriders in P/M George Allegrezza wrote about the waverider article in the June 1993 issue of Popular Mechanics. and Jeffrey Flamm responded I would like to add my 2 cents worth. The waverider concept, at least how it applies at the University of MD, is based on total vehicle optimization. I believe the waverider in PM is a Mach 6 viscous optimized waverider generated by a code named MAXWARP (Maryland Axisymmetric Waverider Program). That is to say, the waverider depicted is optimized for maximum lift to drag ratio only in it's stripped down form. By adding wing tips, ailerons, engine inlet, etc. to this true waverider may or may not create another waverider. (Recall that a waverider is so called because it rides the shock wave which it creates). However, this work WILL tell us a great deal about off design configurations, which is very important since no one fly's on design, well maybe for a split second :^). There has been work on the generation of engine integrated hypersonic waveriders in which the engine was part of the optimization process (this was in an AW&ST article last summer). Current work is also being done on stability and control of waveriders. These are not the only issues we are studying. There are currently 6 students working on waveriders at UMD. From 3D flowfield ananlysis (CFD) to missile design to stability and control. Charles - ------------------------------------------------------ Charles Lind -- lind@eng.umd.edu Hypersonics Research Group Department of Aerospace Engineering University of MD, College Park, MD 20742 - ------------------------------------------------------ ------------------------------ From: urf@ki.icl.se (Urban Fredriksson) Date: Sat, 15 May 93 20:24:25 MET DST Subject: Grob Strato 2C "But the Grob Strato 2C isn't a black project!" I can almost hear you saying. No, on the contrary since they want to sell it. The maker also considers it a low-risk development as all technology is pretty straightforward extrapolation from already known methods. But it compares very well with Boeing Condor, which is so black that it even was missing from Flight International's directory of unmanned air vehicles. Some basic data: Empty weight 5800 kg Max take off weight 11700 kg Span 56.5 m Engines 2 x 300 kW (both at ground level and max altitude) supercharged piston engines Max altitude 26 km Cruise at 24 km 520 km/h Max range 18100 km (not radius) Crew 4 The propellers were recently changed from tractor to pusher arrangement, I'm not sure of the number of blades, but I guess they'll retain their 6 m diameter. This war to leave sensors in the forward fuselage undisturbed by the propellers as well as improving wing efficiency. One flight profile is illustrated in Mach issue 52. Take off weight 9960 kg, landing 6700 kg, radius 3500 km. Climb to cruise altitude 18 km, transit to mission area (for example the South Pole), climb to mission altitude of 24 km and stay there 8 h followed by descent to 18 km and return to base. A diagram that plots endurance vs altitude is a nearly straight line, from 30 h at 21 km, to 80 h at 12 km. - -- Urban Fredriksson urf@icl.se ------------------------------ From: Dave Cox Date: 15 May 93 16:00:40 PST 8 PDT Subject: Sea Shadow in LA Times The 5/15/93 LA Times business section has a brief story on the Sea Shadow. No new info, but 2 nice color pictures. The top front of the starboard hull is just visible below the water in one of them. - --dave ------------------------------ End of Skunk Works Digest V3 #43 ******************************** 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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