Boeing X-51

The Boeing X-51 is a scramjet demonstration vehicle expected to fly by 2009 at hypersonic speeds close to Mach 7 (around 8,050 km/h). The X-51A program is a consortium of the US Air Force, DARPA, NASA, Boeing and Rocketdyne. The program is managed by the Propulsion Directorate within the United States Air Force Research Laboratory (AFRL). [cite web |url=http://www.boeing.com/news/releases/2007/q2/070601a_nr.html |title=Successful Design Review and Engine Test Bring Boeing X-51A Closer to Flight |publisher=Boeing |date=2007-06-01] The X-51A is a descendant of earlier efforts including the Advanced Rapid Response Missile Demonstrator and the liquid hydrocarbon-fuelled scramjet engine developed under the USAF’s HyTech program. The scramjet flight test vehicle was designated X-51 on 27 September 2005. [ [http://www.pr.afrl.af.mil/mar/2005/sep2005.pdf Propulsion Directorate Monthly Accomplishment Report] , US Air Force, September 2005.] The X-51 is carried aloft by a B-52 bomber and then launched with the aid of a solid rocket booster. DARPA views X-51 as a steppingstone to Blackswift, a flight demonstrator that is slated to take off from a runway around 2012. [cite web |url=http://news.yahoo.com/s/space/20080908/sc_space/nasahelpingusairforcegearupfor2009x51flights |title=NASA Helping U.S. Air Force Gear Up for 2009 X-51 Flights |publisher=Space.com |date=2008-09-08<]

Testing

Ground tests of the X-51A began in late 2006. A preliminary version of the X-51, the "Ground Demonstrator Engine No. 2", completed wind tunnel tests at the Langley Research Center on July 27, 2006. [ [http://www.spacedaily.com/reports/PWR_Completes_Mach_5_Testing_Of_Hypersonic_Propulsion_System_999.html Completes Mach 5 Testing Of Hypersonic Propulsion System] . Accessed 28 July 2008.] In April of 2007 an entire flight was simulated. The result was positive. Two ground test engines will be built. Testing will continue until 2008.

During the flight demonstrations, a B-52 will carry the vehicle to an altitude of about 35,000 feet and then release it. Initially propelled by an ATACMS solid rocket booster, the scramjet will take over at approximately Mach 4.5, and the vehicle will accelerate to a flight speed near Mach 7. [ [http://www.boeing.com/news/releases/2007/q2/070601a_nr.html Successful Design Review and Engine Test Bring Boeing X-51A Closer to Flight] . Accessed 28 July 2008.]

In 2009 a total of 4 test flights are scheduled.

Specifications

aerospecs
ref=
met or eng?=eng

genhide=Y

crew=
capacity=
length m= 7.9
length ft= 26 [http://www.globalsecurity.org/military/systems/aircraft/x-51.htm]
length in=
span m=
span ft=
span in=
swept m=
swept ft=
swept in=
width m=
width ft=
width in=
height m=
height ft=
height in=
wing area sqm=
wing area sqft=
swept area sqm=
swept area sqft=
empty weight kg= 1,814
empty weight lb= 4,000
gross weight kg=
gross weight lb=

eng1 number=
eng1 type=
eng1 kw=
eng1 hp=
eng1 kn=
eng1 lbf=
eng1 kn-ab=
eng1 lbf-ab=
eng2 number=
eng2 type=
eng2 kw=
eng2 hp=
eng2 kn=
eng2 lbf=
eng2 kn-ab=
eng2 lbf-ab=

perfhide=Y

max speed kmh=
max speed mph=
max speed mach= 7+
cruise speed kmh=
cruise speed mph=
range km=
range miles=
endurance h=
endurance min=
ceiling m=
ceiling ft=
climb rate ms=
climb rate ftmin=

References

ee also

*Scramjet
*Waverider

;Related development
*Boeing X-43

External links

* [http://www.boeing.com/defense-space/military/waverider/index.html X-51 WaveRider page on Boeing.com]
* [http://www.popularmechanics.com/technology/military_law/4203874.html Hypersonic Cruise Missile: America's New Global Strike Weapon]
* [http://www.aviationweek.com/search/AvnowSearchResult.do?reference=xml/awst_xml/2007/05/07/AW_05_07_2007_p93-01.xml&searchAction=display_result Pratt & Whitney Rocketdyne Scramjet Excels in USAF Tests]