Mach-3 SR-71 Blackbird’s HOT COCKPIT

Blackbird onboard USS Intrepid – Photo © Xavier Cotton http://www.passionpourlaviation.fr

As you may have heard, the mythical Lockheed SR-71 Blackbird was a strategic reconnaissance aircraft able to fly at more than Mach 3 – Mach 3.3 ie around 3,500 km/h; or 1,900 kts; and at a maximum flight level of… FL 850 or 26 kilometers high!

The Blackbird indeed had a unique flight envelope with a particular doghouse plot (since she could not exceed 3.5 G), and an exceptionnal coffin corner limited by her CIT – Compressor Inlet Temperature of 427°C maximum.

This aircraft was also unique for her engines were two J58 ramjets fuelled by JP-7 especially refined for extreme flying purpose. This special fuel could drip and leak abundantly as the airframe made up of titanium was retracted while taxiing, and became airtight only when it got its operating shape while flying very fast and very high because of the air density, and surrounding pressure plus the heating caused by the air friction at such speeds. In short, the whole structure considerably expanded when airborne.

The irony – I heard it on the grapevine, or read it somewhere on the web – that titanium which turned into dark blue while flying (SR-71s probably deserved those unofficial other nicknames « Bluebird », or « Habu » viper) was « imported » from… USSR!

Pilots must have taken significant risks inherent in flying such an aircraft as mentioned in this previous post. These pilots used to fly over the USSR to take strategic reconnaissance photographs during the Cold war. They wore pressurized spacesuits so that their blood could not boil in case of decompression or ejection at such altitudes.

The Blackbird travelled faster than a rifle bullet, and the air friction could have melt aluminum-skinned aircraft. At Mach 3.2, fuel cycled behind the chine surface in order to cool the aircraft! The inner windshield temperature could reach 120°C even though a heavy-duty cooling system was on a full function. On landing, the outside temperature of the canopy could reach 300°C, and it must have been far beyond on the fuselage, and wing surfaces while flying at high speeds. The pilot could feel the heat behind his protective gloves!

Special thanks to Xavier Cotton for the Blackbird photos. Please, visit his website on http://www.passionpourlaviation.fr

MACH-20 AEROSPACECRAFT

New-York to Los Angeles in 12 minutes… It would have been a record-breaker, had it worked:

The DARPA and USAF FALCON project might give anybody the thrill of speed as this « aerospacecraft » has been designed to reach Mach 20 i.e. around 20,000 km/h; 5.6 km/s; 10,800 knots; or 12,400 mph depending on the air temperature, and the altitude which might be above at least FL900!

DARPA USAF FALCON HTV-2 hypersonic aerospacecraft - 22 April 2011
DARPA HTV-2 - 22 April 2011 ---- Photo: DARPA, US Federal Government

Unfortunately, the project seems to encounter major difficulties as the last test which unfolded on August 11, 2011 failed again. The previous one – also on an HTV2 – had failed in April. Click on the right-hand side picture to get further information on the first test. The Blackswift (HTV-3X)  had been designed by ATK; Boeing; Lockheed Martin; and Skunk Works to provided a strategic strike anywhere in the world within an hour. It was cancelled due to a lack of funds (see the HTV-3 shown in the following video):

 


 

  • DARPA stands for Defense Advanced Research Projects Agency
  • FALCON stands for Force Application and Launch from CONtinental United States
  • FL stands for Flight Level (FL x 100ft = altitude)
  • HTV stands for Hypersonic Test Vehicle or Hypersonic Technology Vehicle
  • RCS means here in the videos: Reaction Control System (and not Radar Cross Section)

Click on the picture below, and then on the blue arrows to watch the different phases of light:

Flight Overview slide, MACH-20 DARPA AEROSPACECRAFT
Flight Overview slide - Interactive picture: DARPA, U.S. Federal Government

Volcanic ash posing a threat to flight safety

Sunday 5/22/2011 – Breaking news:

The Grimsvötn volcano began erupting yesterday. It is located underneath the uninhabited Vatnajokull glacier in southeastern Iceland. As it has been sending ash into the skies up to flight level 650 i.e. 65,000 ft or around 20 kilometers or 12 miles.

The European fleets might be grounded due to the spreading of an ash cloud which is forecast to drift over Scotland on Tuesday – May 24, 2011 – and expected to reach France and Spain by Thursday or Friday. Here is an interesting short documentary about how the scientists examine the volcanic ash, and how they determine that it can pose a threat to aircraft.

Watch the video:

Boeing X-51A Waverider at Mach 6