posted on Jul, 27 2014 @ 03:40 PM
Well, my day job put me into radio silence for a few days, but now I’m back. Let’s take the Portugal sightings at face value and see where that
Initially, I carried the hypothesis that this new vehicle might be a transatmospheric vehicle (TAV) boosting out of the atmosphere on a ballistic
trajectory, performing a lifting entry, and transitioning to a hypersonic glide. There are two factors that argue against this: First of all, the
objects came in off the Atlantic and went feet dry at the coast on a heading just about due East. If you assume that the vehicle would have launched
from the US or US controlled territory, there is virtually no way that it could have been heading directly 090 degrees when it crossed Portugal’s
coastline. This is due to orbital mechanics considerations, which I will skip over for the time being. Secondly, the fact that it did a fairly short
radius turn on an apparently constant speed trajectory within the sight of one of the ground witnesses means that it was inside the atmosphere at that
point. Assuming the two Portugal sightings were of the same object, it was an airplane, not a spaceplane.
Unlike a spaceplane, when an airplane moves from point A to point B, it is continuously pushing all the air molecules between A and B out of the way.
That results in continuous drag, which requires continuous thrust. A reasonable conjecture is that the continuous green glow is the visible signature
of the continuously operating propulsion system.
Given that it was an entirely endoatmospheric vehicle, there is no good reason the propulsion system would use rocket power and a lot of good reasons
it would not, so, let’s assume it was an airbreather.
Based on the witness accounts, the vehicle appeared to be moving across the sky about 5 to 6 times faster than commercial jets (which cruise around
Mach 0.9). So let’s guess that the vehicle cruises between Mach 5 to 6, or approximately twice the speed of an SR-71.
Speaking of which, the SR-71 is a good vehicle for comparison. Suppose, for argument, this new girl has about the same wing loading as the SR-71.
That would mean, among other things that it should be able to fly roughly the same subsonic profile for purposes of takeoff, landing refueling, and
formation flying with fighters, as observed. At top speed, flying twice as fast, it only needs ¼ the atmospheric density of the Blackbird, meaning
it wants to cruise at a higher altitude. (If the nominal cruise altitude of the Blackbird is 100,000 ft, then the new girl would fly at about
I would expect that the new girl would have at least as good a supersonic L/D as the Blackbird—in fact probably slightly better, what with
improvements in computational fluid dynamics, and all. That being the case, it would have the same or slightly better specific fuel consumption as
the Blackbird (i.e., burn the same mass of fuel per unit mass of aircraft, per unit of distance travelled).
Aerodynamic heating on the nose and leading edges scales like the Mach number, cubed. So, doubling the flight Mach number from 3 to 6 will increase
the heating by a factor of 8. This means the nose and leading edges undoubtedly have thermal protection materials on the outer surfaces, beyond what
the Blackbird had. Mach 6 is too slow to justify ablative materials, so I would expect something like shuttle tiles over an actively cooled load
bearing structure. Active cooling is no doubt accomplished by circulating the fuel before burning it.
Flying twice as fast as the Blackbird with the same L/D basically means that you have to burn twice the mass of fuel per unit distance travelled, and
this is where I think they had to get creative. The normal way to get twice as much fuel burn would be to keep the fuel/air ratio constant and pass
twice as much air through the engine. I don’t think there’s any internal aerodynamic flow problem with flying turboramjets like the JT11-D at Mach
6, compared to Mach 3, and I have to assume that the JT11-Ds on the SR-71 were nearly optimized for their ability to extract thrust per unit mass. So
you couldn’t just open up the inlets and let twice as much air in and expect them to stay lit at Mach 6.
To get twice as much thrust per unit of distance travelled, without increasing the size of the engine, you have to solve two problems, simultaneously.
You have to be able to sustain stable combustion of your main fuel (presumably JP-7) well outside of its normal fuel/air ratio AND you have to be
able to effectively double the flame front speed of your propellant/oxidizer mixture.
What Zaph is hinting is that they are injecting a combination of fuel + oxidizer into the combustion process when the vehicle is at high speed cruise.
The addition of oxidizer pushes the fuel/oxidizer ratio back towards stoichiometric, where it is most efficient. I surmise that the “fuel” they
are injecting is chosen not just for its heating value, but also for its ability to improve the combustion speed. Tri Ethyl Borane (TEB) is the
obvious choice since it is highly pyrophoric; that means that when it is injected, it burns everywhere at once. The flame front doesn’t have to
propagate from one end of the fuel/air mixture to the other. TEB is slightly more energetic than straight hydrocarbon fuels, so there shouldn’t be
any efficiency loss. It’s also already in production and has heritage from the SR-71 program. The oxidizer could be any one of a number of
storable substances. The usual suspects would be Nitrogen Tetroxide (NTO), Hydrogen Peroxide, (H2O2), or perhaps Nitrous Oxide (NOS).
One big problem with use of Diborane aircraft fuels back in the 1950s was that one of the products of combustion in a Nitrogen rich environment (like
the atmosphere) is Boron Nitride (otherwise known as Cubic Boron Nitride—CBN). CBN is an industrial abrasive, second in hardness only to diamonds.
Burning Diborane fuel in a turbojet was equivalent to continuously sandblasting the inside of the engine. They usually had to be rebuilt after each
flight. Injecting the Boron rich fuel into the ramjet duct bypasses this particular problem.
Overall, Zaph is presenting a perfectly consistent and logical description of a Mach 6, ISR aircraft. I have no idea why the naysayers don't think he
knows what he’s talking about.