SR-72 Confirmed: Mach 6 Project Blackswift

a reply to: anzha
In other words pull your fingers out and start getting prototypes ready..

a reply to: anzha

great find anzha

LM should just show that one already

a reply to: Blackfinger

Stability during maneuvering would kinda imply there's something flying.

a reply to: anzha

Or simply that such engines hate non-uniform flow of the sort they would need to tolerate if maneuvering...

Going on 14 y/o rumors of a semi-operational aircraft and still no official roll out, this thing must be breaking records every time it flies.

a reply to: StratosFear

Or we're talking about more than one platform, with one being replaced since it flew.

Of course! You guys were not referencing a green lady when this thread came out IIRC. Sounds like the design has gone through an A, B, maybe C and D model. Doesnt seem like there could be more than a squadron of them out there if that, 4-5 maybe between Groom, Guam and some other airbase they could stay far away from prying eyes.

If someone good do a sketch of what it supposedly looks like it will help..

Here was one of the concepts for the C-21 replacement:

a reply to: Masisoar

Very Concorde-esque.

Very nice also

a reply to: Catch_a_Fire

Don't think it was intended to be much of a super duper high speed recon bird, more of a package delivery service kind of thing. Who knows. ¯_(ツ)_/¯

originally posted by: Zaphod58
a reply to: StratosFear

Or we're talking about more than one platform, with one being replaced since it flew.

hmmm... fastmoving yellow light replaced by the green lady?

a reply to: Masisoar
Heard that as well that the Green lady started off as a civil bird before pressed into military service.Dont think shes one of the popular manufactureres either.

a reply to: Blackfinger

*cough*Valkyrie*cough*, maybe?

I haven't posted one of these in a while.


Experimental investigation of the ignition characteristics of vaporized RP-3 kerosene in supersonic flow

Authors:

Yang et al

Abstract:

The ignition characteristics of vaporized RP-3 kerosene were experimentally investigated in a cavity-based Mach 2.52 scramjet combustor. The simulated flight condition was Ma 5.5 at 25 km, while the entrance had a stagnation temperature of 1486 K and a total pressure of 1.6 MPa. With high-speed photography and chamber pressure measurement, the effects of fuel temperature on ignition performance were studied under a lean fuel condition, and the mechanism of ignition failure during the fuel temperature increasing was investigated. The results showed that increasing the injection temperature could accelerate the atomization and evaporation processes of the fuel droplets, reduce the ignition delay time, and enhance combustion in the cavity. However, a critical point (about 567 K) was found in vaporized kerosene ignition. When the injection temperature approached this point, the phase of the kerosene jet transited sharply, and the penetration depth increased. It decreased the fuel-air equivalence ratio in the cavity, deteriorating the reaction environment and causing ignition failure. The blow-out process had a similar evolution at different injection temperatures. Flame in-cavity was repeatedly stretched and merged with dissipating heat, and eventually blown off near the bottom. The flame residence time was closely related to the discharge time of the spark plug.

www.sciencedirect.com...

a reply to: UNFalcon
Does look a little like the Fastmover "supposedly" seen at Groom..

a reply to: Blackfinger

i think its a safe bet that if she is manned that the windows will be allot smaller than we are used to seeing on aircraft like the F22 and 35 where there is a nice open canopy

isnt 52 or 53 degrees of wing sweep best for hypersonics? Maybe that shape shifting flap/wings are in use in a crazy way.

my bet is that it will be a long tube with really swept back delta wing/body with razor sharp leading edges using carbon-carbon and maybe active cooling using for the hot spots on the aircraft with pipes under the skin that preheat the fuel and carries the heat away from the skin of the aircraft.

i think it will be AT LEAST a 2 man show, 1 guy flying and the other 2 for WSO and other system operations.

and it could use some fancy science at the inlets for better power, not talking boranes but electricity as a plasma tp protect the skin of the aircraft.

i have seen one hypersonic 'thing' flying once and it was so fast it was shocking.

a reply to: penroc3

Razor sharp edges are generally regarded as bad for sustained hypersonic flight because of thermal management. Aerodynamically, we want sharp edges for greatly reduced drag. Stagnation point heating, however, is inversely proportional to the square -root of the leading edge's radius of curvature. At sustained hypersonic speeds, we'll need help managing thermal loads. So the thicker, the better.
Thick will also help manage aerolastic loads like divergence and flutter (either of which may very easily rip apart our wings at hypersonic flow-speeds, regardless of thermal performance). We'll need to find a healthy compromise between less drag, and not dying. It won't be "razor-sharp".
There are other reasons that we won't really delve into specifics here that will influence leading edge geometry, but essentially, it's because we will want a "window" to look through.

Carbon-carbon will still suffer ablation. That's bad for a vehicle you want to use repeatedly. Reinforced carbon-carbon will be great for its ability to withstand thermal-loads without losing strength or rigidity, but we have to protect it from ionization (more weight) and it will require constant replacement or refurbishment after a relatively small number of flights. Making a structure out of this material would not be useful (for a reusable platform)

Carbon -carbon is greatly heat resistant compared to most materials, but it is also a great conductor of heat. So we still have to insulate our hypothetical aircraft structure from any carbon -carbon we are using at the edges. That means thermal blankets or a more complicated system of pipes and pumps which you suggest. So we would need a high-pressure/velocity pump and a plumbing system which would then need be absolutely failure- and leak-proof at risk of catastrophically losing the vehicle.
All of that means a lot of weight, and in the case of active cooling, introducing much higher costs and potential avenues for single -point failures (both extremely undesirable). The main drawback of increased weight is payload displacement. Every pound of thermal blanket (or pumps and pipes, or any thermal management system), is a subtraction of a pound of fuel and/or other useful mission payload.

Maybe use an evolution of ceramic tiles that were used on he shuttles..What does the Boeing X37b use?
Im thinking something exotic melded with an existing high powered engine package..
Some good stuff in here..
NASA

a reply to: Blackfinger

I've sent recommendations to DARPA about looking into the feasibility of duct taping blocks of dry ice to the leading edges of its high speed test platforms for heat dissipation. In return, they keep sending me this picture: