The SR-71 is NOT a ramjet. It has a specially designed turbojet which bypasses compressed air after the last compressordirectly to the afterburning exhaust duct, whereas a conventional turbofan bypasses air after the first compressor stage.
The F-22 is the first fighter designed to supercruise, but tops out around 1.7 M, with afterburners.
Concord, on the other hand, has been supercruising since the 70's (gives new meaning to superfly:). Concord will apply afterburners at take-off as assurance against any engine-out failures, and afterburns through to about 1.1M to get past the high drag transonic region (as an aircraft approaches the speed of sound, the pressure drag reaches its highest, like a boat catching up with its bow wave prior to planing). After passing through the transonic region, Concord releases the afterburners and continues on to cruise at 2.5M.
The speed of sound is purely a function of temperature and has no relation to density!
a=sqrt(gamma*R*T)
At high altitude, the air is very cold, therefore the speed of sound is lower. As you get very high, beyond the stratosphere, the temperature of air increases. However, the air at extremely high altitudes is no longer dense enough to be considered a continuum and the question of speed of sound is moot, since there is none.
Airliners cruise at high altitudes because the lower density and temperature result in lower drag, due to a reduction in the Reynolds number,
Not to diminish the original intent of the post (exceeding Mach 5 is a significant breakthrough for airbreathing aircraft), but Mach 2.1 is no significant feat.
Many fighter aircraft can sprint up to <b>2.5 M</b> or better (full afterburners), and <b>Concord</b> can supercruise at <b>2.5 M</b>. The <b>SR-71</b> supercruises at a little over <b>3.0 M</b> with engines which are actually designed to efficiently maintain afterburning during cruise, and the <b>SU-27</b> can reach <b>3.0 M</b>, but the engines have to be replaced afterwards:-)
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I can't believe I'm wasting my time responding to your crap!!!
The F-22 is the first fighter designed to supercruise, but tops out around 1.7 M, with afterburners.
Concord, on the other hand, has been supercruising since the 70's (gives new meaning to superfly:). Concord will apply afterburners at take-off as assurance against any engine-out failures, and afterburns through to about 1.1M to get past the high drag transonic region (as an aircraft approaches the speed of sound, the pressure drag reaches its highest, like a boat catching up with its bow wave prior to planing). After passing through the transonic region, Concord releases the afterburners and continues on to cruise at 2.5M.
a=sqrt(gamma*R*T)
At high altitude, the air is very cold, therefore the speed of sound is lower. As you get very high, beyond the stratosphere, the temperature of air increases. However, the air at extremely high altitudes is no longer dense enough to be considered a continuum and the question of speed of sound is moot, since there is none.
Airliners cruise at high altitudes because the lower density and temperature result in lower drag, due to a reduction in the Reynolds number,
Re=rho*V*D/u
Not to diminish the original intent of the post (exceeding Mach 5 is a significant breakthrough for airbreathing aircraft), but Mach 2.1 is no significant feat.
:-)
Many fighter aircraft can sprint up to <b>2.5 M</b> or better (full afterburners), and <b>Concord</b> can supercruise at <b>2.5 M</b>. The <b>SR-71</b> supercruises at a little over <b>3.0 M</b> with engines which are actually designed to efficiently maintain afterburning during cruise, and the <b>SU-27</b> can reach <b>3.0 M</b>, but the engines have to be replaced afterwards
...to name a few.
Stole it from NeXTStep? Bone up on your history bud.