DARPA and the U.S. Air Force have been interested in improving the speed capabilities of aircraft for a long time. Given that the fastest speed ever attained by an airplane/jet is just over 3,500 mph, which is around Mach 4.6. (Mach 1 = 761 mph), attempts to raise the speed have met with engineering challenges. The latest speed test occurred when DARPA and the U.S. Air Force put forth the FalconHTV-2 Flight.
DARPA
The Defense Advanced Research Project Agency or DARPA is a U.S. government agency that takes on theoretical projects in science. Formed in 1958 to prevent a strategic surprise that would affect the national security of the U.S., they have had many innovations, but their most famous project was creating the Internet back in 1968.
The Hypersonic Falcon Project
The Hypersonic program started in 2003. This is a two-part program joint program between DARPA and the US Air Force. The first part is the Hypersonic Weapon System (HWS). It is set to develop a reusable, rapid-strike deployment system. It is now called the Hypersonic Cruise Vehicle (HCV) system.
The second part develops a launch system capable of getting an HCV to reach cruise speeds of 13,000 mph. This would mean that a flight between Los Angeles and New York would take 12 minutes. The Falcon project is also developing a launch vehicles allowing small satellites to get into earth orbit.
The 2010 Flight
Two flights have taken place to assess the progress of the program. The first flight took place in April 22, 2010. The Falcon HTV-2 is part of a rocket capsule. When the rocket reaches an altitude just under orbital heights, or about 62 miles, the HTV-2 separates and it begins its flight. The glider traveled at 7,000 mph. But nine minutes into the flight, the computer autopilot issued a flight termination command. This command takes place when the autopilot detects undesirable or unsafe flight conditions.
The 2011 Flight
A second flight occurred on Aug. 11, 2011. Unfortunately, nine minutes into this flight, the autopilot also terminated the flight because there was a problem maintaining a safe flying condition. Apparently, it was weaving and rolling. Therefore, the autopilot forced the plane into the Pacific Ocean to prevent any damage on land and to avoid civilian casualties.
Conclusions
At this point after two tests, there are several unanswered questions. But here is what they do know.
The aircraft transitioned into Mach 20 speed. This transition represents critical knowledge about the behavior of the glider and a control point in the maneuvering to reach an atmospheric hypersonic flight. Flight engineers know how to boost the aircraft to near space altitudes. In addition, they know how to put the aircraft into a hypersonic flight. However, there are problems with the construction of the glider that have not been resolved.
At the speeds that the HTV-2 was flying, there are metal, heat and atmospheric related problems that currently make the plane unstable. Engineers and scientists have to make adjustments in the physical construction and metal implementation to make the project a success.