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How We Might Have Scramjets Sooner than Expected
loralai writes "Recent breakthroughs in scramjet engines could mean two-hour flights from New York to Tokyo. This technology, decades in the making, could redefine our understanding of air travel and military encounters. 'To put things in context, the world's fastest jet, the Air Force's SR-71 Blackbird spy plane, set a speed record of Mach 3.3 in 1990 when it flew from Los Angeles to Washington, D.C., in just over an hour. That's about the limit for jet engines; the fastest fighter planes barely crack Mach 1.6. Scramjets, on the other hand, can theoretically fly as fast as Mach 15--nearly 10,000 mph.'"
F-16 top speed at altitude: Mach 2+
F-22 top speed at altitude: Mach 2.42 (officially...it's reported it can exceed Mach 4)
F-18 top speed at altitude: Mach 1.8+
I actually couldn't find a modern jet fighter that COULDN'T exceed 1.6 (at least within my aforementioned 2 seconds of research)
Of course, that doesn't diminish the insanity of Mach-15, but still.
Oh yeah, if you turn, your heart will forcibly exit your body via your anus before exploding. Have fun.
Yes, infact I knew someone who use to fly those things and they weren't allowed to fully throttle up. He also said that during normal missions the plane would damage itself when going the faster speeds. Now of course this is all at someones word, so I have no written proof. Also there would be a slight correction, the SR-71 didn't have "normal" jet engines. SR-71 used ramjet engines, scramjets employ similar but much more advanced technology.
"Hold! What you are doing to us is wrong! Why do you do this thing?"
Of course materials will have to advance further, and not just structural components (which might well strip off the plane or warp at speeds too far past a few Mach) but new fuel mixtures will have to be worked out. This was similar to the requirement to add Cesium to current fighter plane fuel along with a few other rare elements to raise its flash point. Experimental planes blowing up because the fuel overheated or certain electronics received more heat than they could tolerate is nothing new, but the production models will obviously have to have gotten past that point when they roll out :)
I wager this technology has been near perfected sometime ago, but as with all things, it was probably kept back to be used in case of sagging sales due to rights abuses at airports (Atlas has Shrugged, and it is visible in that people are avoiding airports now because of the downright abusive behaviors of the TSA and federal shock troops there to protect us from incompetent unshaven twits with box cutters and toothpaste.
Seriously, this will be the carrot on a stick to dissuade people from using other less regulated means of transportation. Obviously L.O.S.T. was ratified recently in Congress to restrict private sea travel... now only warships and those with "permission papers" will be "allowed" to travel, and who knows what else is coming. Free travel is becoming far less so.
" What luck for rulers that men do not think" - Adolf Hitler
Actually that brings up a good point. I can't believe they're wanting to go faster then the SR-71, or even as fast. It had the problem about its fuel tank sealing up at high speeds, but on the ground it leaked badly. Problem was that they didn't have a material that could seal the tank and still be flexible while not melting off at those high temperatures. Have they solved this problem?
If not then maybe they want the scramjet because its quiet(er) then the ramjets of old? I know tons about the SR-71, but I haven't really researched much on scramjets beyond the mythological Aurora(fabled successor to SR-71). Does a scramjet produce a less significant sonic boom then a ramjet?
"Hold! What you are doing to us is wrong! Why do you do this thing?"
I fly all the time. From Hawaii, all over the country for work. I have a scraggly beard and I usually fly in sweat pants and a t-shirt. I look ruffled at best, and often also wear tie died shirt. I have never been hassled by TSA. Never. In fact, TSA is usually really polite and helpful. The trick is, I try to be polite and refrain from asshole behavior. If you are going to start shit with the TSA, then you will have a bad experience. If you act polite, even minimally so, it's a non issue to get through security. And I carry my iPhone with me, which is based off of BSD while not quite linux is still an OSS *nix variant. So I'm cool. ;-)
Horns are really just a broken halo.
I'd like to add that while the SR-71's top speed may technically be classified, but anyone with a photo, a protractor, and a scientific calculator can figure out at least the top design speed.
When an object like the black bird travels at supersonic speeds, an oblique shock is formed starting at the tip of the plane. The angle that the shock wave forms is proportional to the mach number, and they are related in a relatively simple equation. The faster you go, the tighter the shock.
It is wise to keep the wingtips inside of the shock, lest they be ripped off. It is logical to assume that the designers would put the wingtips as close to the shock as possible to maximize the wing's area. Therefore, by drawing a triangle from the tip of the plane to the tip of the wings, and measuring the angle, you should have a pretty good first order approximation of the maximum speed of the blackbird. I don't recall the number off the top of my head, but if someone wants to figure it out, the math is pretty simple.