(no change in this background section since 7/14 report)
DC-X is a low-speed flight regime testbed for a proposed reusable rocket- powered Single Stage To Orbit (SSTO) transport, McDonnell-Douglas Aerospace's "Delta Clipper". DC-X is intended to prove out rocket-powered vertical takeoff, nose-first lifting-body to tail-first flight transition, and tail- first landing. It is also intended to prove out rapid turnaround of a reusable rocket by a minimal ground support crew.
DC-X has already pretty much proved out rapid low-cost development of an advanced aerospace X-vehicle type engineering testbed by a small highly- motivated engineering team on a tight budget. Of course, that's been done before -- just not recently.
DC-X stands 40 feet tall, is 13 feet across the base, and is roughly cone- shaped, with a circular cross-section forward blending into a square base. The vehicle has four maneuvering flaps, one set into each side near the base, and sits on four landing legs. DC-X masses 22,300 lbs empty and 41,630 lbs fully fuelled, and is powered by four 13,500 lb thrust Pratt & Whitney RL-10- A5 liquid oxygen/liquid hydrogen rocket motors, each able to gimbal +- 8 degrees. The RL-10-A5 is a special version of the RL-10-A designed for wide throttling range (30% to 100%) and sea-level operation.
The single DC-X vehicle was officially rolled out of its construction hangar at MDA's Huntington Beach CA plant at the start of April, then trucked out to White Sands, New Mexico for ground and then flight tests.
The DC-X vehicle was taken out of storage and trucked over to the White Sands Missile Range (WSMR) flight test site last Friday, July 16th. Once at the site, DC-X was set upright on the launch pad. (An interesting aside -- this pad was originally the concrete base laid down for lifting a Shuttle orbiter onto its 747 carrier aircraft, back when it was thought that WSMR might be used as a regular alternate landing site. The amount of blown dust they had to clean out of the orbiter the one time they landed there has convinced NASA they really don't want to use White Sands again if they can help it.)
Now that flight test site setup is done and DC-X moved, the DC-X crew is running a series of ground tests to make sure everything made it over intact and is hooked back together properly. The ground tests should culminate in a "burp test" sometime next week, a four-second firing of DC-X's engines on the launch pad to check that all the plumbing is OK.
The first "bunny hop" flight stability test series should begin shortly thereafter. These hops will consist of takeoff, sideways transition of several hundred feet, and landing, done under varying wind conditions.
A lot of people will be keeping their fingers crossed during that initial
bunny hop, as it will be the first real-world test of DC-X's stability at low
speed and altitude. Between crosswinds, "ground effect" (aerodynamic
interactions between the rocket plumes, the ground, and the vehicle body),
the known fact that computer sims of turbulent airflow are at best black
magic, and a general awareness of how much Murphy loves first flights, the
Mylanta
Note that the "bunny hop" series will be restricted to the thirty or so DC-X test crew members plus WSMR support personnel. No media, no VIP's, no public allowed -- not nobody, not nohow. Any stories you may have heard about the public getting in for these are, alas, wrong.
First official DC-X flight will actually be the initial flight of the second test series, reaching higher speeds and altitude. This will be the one with speeches, hoopla, VIP's, and media coverage -- but still no admission of the general public. Chances are good for TV coverage, between NASA Select, local TV stations, and the national networks. Chances are also good that you'll be a whole lot more comfortable watching it on TV at home, as the test site is fifty miles of back road into a military reservation, run under military security, under the summer New Mexico desert sun. You'll likely have a better view on TV too, since the "VIP" viewing site will be five miles from the pad.
The end-for-end transition maneuver won't be tried until the third, final flight test series.
Tentative dates for the start of the first and second flight test series are still July 29th and August 9th, respectively. The exact dates depend on a lot of factors and likely won't be known until a couple days beforehand. Some delays are likely, however, as the pad area has to be cleared anytime there are lightning strikes within five miles (a fairly standard safety precaution when working on large rockets) and New Mexico is in the midst of monsoon season, with thunderstorms common.
The current DC-X program is funded through flight test and data analysis this fall, and ends after that. There is an ongoing effort to get the US Congress to fund a three-year followon program, currently called SX-2 (Space Experimental 2). This tentatively looks like being a suborbital vehicle powered by 8 RL-10-A5 engines, capable of reaching Mach 6 (about 1/4 orbital velocity) and 100 miles altitude, built with orbital-weight tanks and structure, and able to test orbital grade heat-shielding.
The SX-2 program goal will be to demonstrate all remaining technology needed to build a reusable single-stage-to-orbit vehicle. Once SX-2 has been tested, all that should be necessary to produce a functioning reusable SSTO is to scale up the SX-2 structures and install new larger rocket engines.
Proposed FY '94 funding for SX-2 startup is $75 million. The money would come out of the $3.8 billion BMDO budget already pretty much agreed on for the coming year. Total SX-2 program cost over the next three years would be very much dependent on the contractor chosen and the details of the design, but would be on the order of several hundred million. This is the same order of magnitude as typical recent X-aircraft programs such as the X-29 and X-31.
SX-2 would start out under BMDO (formerly SDIO), so support from members of the House and Senate Armed Services Committees (HASC and SASC) is vital. The actual name they know SX-2 by is "followon funding for BMDO's SSRT (Single Stage Rocket Technology) program." The specific action we're calling for is for Congress to authorize $75 million in existing BMDO funding for this project next year -- we are not asking for any new funding authority, but rather for reallocation of existing funding toward a DC-X followon.
The SASC marked up their version of the Defence budget yesterday. Preliminary word is that SSTO was mentioned once, alongside NASP and Spacelifter, in a $30m USAF line-item. This is short of what we'd hoped for, but by no means disastrous. SSTO was at least mentioned, and on an equal (albeit underfunded) footing with NASP and Spacelifter. What this means is that we now need to go all-out on the House side, with an eye toward establishing our position there before the final House-Senate conference.
With the Senate giving us very little of what we need, Representative Patricia Schroeder's HASC Research & Technology Subcommittee markup (and the full HASC markup to follow) become more important than ever.
Schroeder's subcommittee is now supposed to mark up this coming Monday, the 26th. I've checked my notes, and the first "for sure" date I have for this key markup was back on May 19th, so a certain skepticism is excusable -- but at this point HASC R&T has run out of reasons for delay, as the gays-in-the- military issue has been resolved (however messily) and the Senate has already gone ahead and marked up their version of the Defense budget. Chances are that Schroeder and company really will mark, if not Monday, then at least early next week.
One additional factor here: We've mentioned in the past that one appeal to make to Schroeder might be that SSRT Followon would take funding that would otherwise go to weapons development and put it to peaceful uses. Well, we need Schroeder's support real bad, and we understand she would prefer to see specific cuts in BMDO proposed to offset any new spending requested.
SAS is reluctantly taking the step of picking a specific existing program within BMDO and recommending it be cut by $75 million in FY '94 in order to fund SSRT Followon within the overall $3.8 billion BMDO budget. We do not like doing this; our stated mission is to focus solely on the issue of space access. Recommending military budget cuts in areas unrelated to space access is really none of our business.
Nevertheless, we're doing so. After careful consideration, we are recommending that the National Missile Defense portion of the Ground Based Radar development project (BMDO's NMD-GBR), requested at $100m for FY '94, be cut to $25m, and the $75m freed up be allocated to FY '94 funding of SSRT Followon. This is not necessarily a good program to cut, but it seems the least bad among the available options, as the somewhat complementary Theatre Missile Defense, Ground Based Radar development would remain funded at $238m.
SAS members with questions or comments should contact headquarters.
Contact Representative Schroeder plus any member of her HASC R&T Subcommittee whose district is near you by Monday morning. Ask them to fund SSRT Followon at $75m for the coming year (FY '94). Tell them that if they have to take the money out of another BMDO program, reducing the National Missile Defense portion of the Ground Based Radar project (NMD-GBR) from $100m to $25m would be the way to do so.
Followup by contacting Representative Dellums (Chair, HASC) plus any member of the full HASC whose district is near you by midweek, with the same message.
Keep phone calls brief, polite, and to the point - tell whoever answers that you're calling to let them know you support $75 million of BMDO (formerly SDIO) funding for the SX-2 followon to the Single Stage Rocket Technology ("SSRT") program, and that if they have to take the money out of another BMDO program, cutting the National Missile Defense portion of the Ground Based Radar project (NMD-GBR) by $75m would be one way to go. If you feel like it, throw in your favorite reason why SX-2 would be a good thing. If the person who answers wants to know more, answer their questions as best you can, otherwise thank them and ring off.
Letters too should should be brief, polite, and to the point, though you can go into a bit more detail as to why a DC-X followon is good for the country. Keep it under a page and state your basic point at the start.
Don't overdo it, but in general try to know who you're contacting and emphasize benefits likely to appeal to them, given their positions on the political spectrum. Future US aerospace technological competitiveness plus stemming the ongoing US loss of international space launch marketshare should appeal to just about anyone. Reusable launchers in general promise an order- of-magnitude reduction in launch costs, and SX-2 would demonstrate technologies applicable to any reusable launcher, not just Delta Clipper.
Henry Vanderbilt "Reach low orbit and you're halfway to anywhere Executive Director, in the Solar System." Space Access Society - Robert A. Heinlein hvanderbilt@bix.com "You can't get there from here." 602 431-9283 voice/fax - Anonymous -- Permission granted to redistribute the full and unaltered text of this -- -- piece, including the copyright and this notice. All other rights -- -- reserved. In other words, intact crossposting is strongly encouraged. --