Wibbleman posted:

... The ME163 had wings for lift and a rocket for thrust, and worked pretty well for its design envelope.

MrChips posted:

I know it's an abbreviation. And if you can show me an abstract or a paper that refers to this engine as a "SCRamjet" instead of "scramjet", then I'll believe you.

MrChips posted:

The scramjet is pretty much the most likely ticket to affordable, reliable transportation to orbit, especially if researchers can iron out the kinks with regard to burning conventional hydrocarbon fuels.

Sterndotstern posted:

Even though it's a funny place to stick a rotary engine in a heli, I suppose Sikorsky had his reasons for using a 1931-vintage engine for his otherwise modern chopper...

Sterndotstern posted:

Even though it's a funny place to stick a rotary engine in a heli, I suppose Sikorsky had his reasons for using a 1931-vintage engine for his otherwise modern chopper...

LOO posted:

Yeah it is.

Nerobro posted:

Something that hasn't been mentioned yet. The oxidizer weighs something like four times as much as your fuel does. So ditching the oxidizer doesn't just save you "half the weight" it saves you 4/5 of the weight! That has massive effects on structure.

Sterndotstern posted:

Ah, perspective, thanks. I looked up the shuttle tank -- 4/5 of it is hydrogen tank, only the nose piece is oxygen, but the oxygen weighs 6 times as much.

quote:

So the real trick for scramjets is fueling? Currently they use hydrogen, which is hard to package, so what are the dense alternatives?

I imagine trouble with scramjet fuel is the time required to extract energy from combustion. You basically have to use hydrogen fuel because you have less than 1msec of burn time unless you build a really long engine. Even F1 cars have almost 3ms of burn time.

ApathyGifted posted:

Well, Kerosene is already used as rocket fuel (RP-1) and jet fuel. The mass ratio between kerosene and oxidizer is way lower than it is for hydrogen/oxygen (3.5 compared to 8 at the stoichiometric ratio), which is probably the main reason it's used in rockets. Don't know how it is about burn speed, that's not really my area.

Sterndotstern posted:

So if I'm understanding correctly, there are two options for building a SSTO lifter:

1) Use a rocket but lug your oxidizer around with you. This has the advantage of simplicity and atmosphere/speed independence, but taking oxidizer requires a heavier fuselage to carry more weight, which in turn requires more fuel, leading quickly to larger scale craft and increased fuel requirements for a given payload.

2) Use a turbine/ram/scramjet hybrid to burn air to attain orbital speed in the atmosphere. This has the advantage of being relatively efficient for a given payload mass, since a higher ratio of the lifter's loaded weight is used for payload (versus fuel). The drawbacks include the need for a separate thrust system in order to function without atmospheric oxygen and the obvious (significant) engineering hurdles involved in building a craft powered by four separate paradigms of propulsion which must survive mach 25+ speeds within the atmosphere.

Sound about right?

^^^ Fine, how about some UGLY radial engines in charming but ugly helicopters:






Even though it's a funny place to stick a rotary engine in a heli, I suppose Sikorsky had his reasons for using a 1931-vintage engine for his otherwise modern chopper...

sandoz posted:

Jesus... I'd really love to see the shaft arrangement in that thing.

joat mon posted:

H-19 (the middle one)


Westlan Wessex, a turboshaft powered version of the H-34. (the first and last ones are H-34s)

LOO posted:

McDonnell Douglas F-4 Phantom II.

River Raid posted:

One of my dad's friends used to fly H-34s. Said he would piss the bed at night everytime he even thought about having to put one down in water. Since the pilots sit so loving high and the balance of it making it immediately flip when it touches down in it.

sandoz posted:

Jesus... I'd really love to see the shaft arrangement in that thing.

joat mon posted:

H-19 (the middle one)


Westlan Wessex, a turboshaft powered version of the H-34. (the first and last ones are H-34s)

sandoz posted:

I'd be more worried about the driveshaft whirling around between me and my copilot.

LOO posted:

Couple more Phantom shots I like.

pbpancho posted:

blue angels & stuff

ursa_minor posted:

I'm sure you guys already knew all about this - but some guys have been building replicas up in Washington, and they are GORGEOUS.

http://www.stormbirds.com/project/index.html

QuiteEasilyDone posted:

Have some more Angels



Not my best, but I liked them when they were taken

Sterndotstern posted:

These are both fantastic shots and utterly staggering displays of human ability. Nothing impresses the mind like perfect control.

Sterndotstern posted:

On a completely different topic, a while ago I posted that air-burning, air-flying technology reached its logical conclusion in approximately 1965 and stated (somewhat controversially) that we're "done" with aircraft. I never got to ask the obvious follow-up question: Where is the next great unsolved problem for aerospace engineering?

Nebakenezzer posted:

Late to th' party but I'd say making LTA craft reliable and durable. I think the technology is already there; it just needs to be applied.

Of course it's no secret that I'm a airship fanboy so

Nebakenezzer posted:

BeastOfExmoor posted:

Holy poo poo, I had no idea this existed. To make it better I live pretty much right on the approach to Paine Field and more then once have glanced out my window and seen the Dreamlifter. I can't tell if they're currently flying the thing, but I'm going to keep my eyes peeled from now on.

quote:

During flight testing in November 2006, a Cessna 172 being used for a training flight encountered the 747 LCF's wake turbulence while on approach to Boeing Field. The small aircraft was accidentally inverted and lost 1,000 feet (300 m) of altitude before the instructor pilot was able to regain control at just 150 feet (46 m).

quote:

A much-smaller explosive charge would suffice, if it could be exploded directly against the dam wall below the surface of the water, but the major German reservoir dams were protected by heavy torpedo nets to prevent such an attack.

Air Vice-Marshal Ralph Cochrane, Wing Commander Guy Gibson, King George VI and Group Captain John Whitworth discussing the Dambuster Raid in May 1943Wallis' breakthrough overcame this. A drum-shaped bomb spinning backwards at over 500 rpm, dropped at a sufficiently low altitude at the correct speed, would skip for a significant distance over the surface of the water in a series of bounces before reaching the dam wall. Its residual spin would run the bomb down the side of the dam to its underwater base. Using a hydrostatic fuse, an accurate drop could bypass the dam's defences and enable the bomb to explode against the dam.

quote:

Bombing from an altitude of 60 ft (18 m), at an air speed of 240 mph (390 km/h), and at a pre-selected distance from the target called for expert crews. Intensive night-time and low-altitude flight training began.

There were also technical problems to solve, the first one being to determine when the aircraft was at optimum distance from its target. Both the Möhne and Eder Dams had towers at each end. A special targeting device with two prongs, making the same angle as the two towers at the correct distance from the dam, showed when to release the bomb.

The second problem was determining the aircraft's altitude (barometric altimeters then in use lacked sufficient accuracy). Two spotlights were mounted, one under the aircraft's nose and the other under the fuselage, so that at the correct height their light beams would converge on the surface of the water.

quote:

When I was about 150 miles from the Möhne Dam, I could see the industrial haze over the Ruhr area and what appeared to be a cloud to the east. On flying closer, I saw that what had seemed to be cloud was the sun shining on the floodwaters.
I looked down into the deep valley which had seemed so peaceful three days before [on an earlier reconnaissance mission] but now it was a wide torrent.

The whole valley of the river was inundated with only patches of high ground and the tops of trees and church steeples showing above the flood. I was overcome by the immensity of it.

Vitamin J posted:

Dambusters!

azflyboy posted:

After the team experienced a fatal crash while practicing for a show in 1999 (caused by a pilot blacking out in a high G turn), the Navy considered forcing the team to wear G-suits, but relented after it was determined that the accident pilot was suffering from a rib injury that kept him from tensing up properly during flight.

LOO posted:

Sterndotstern posted:

I'll see your B-36 and raise you a B-36 with a B-58 back.
http://www.youtube.com/watch?v=Pxrwpur_Op8&feature=related

LOO posted:

More stuff.

Nebakenezzer posted:

That's some beautiful camo. Is it real? If so, what's it for?