AHC/PC: X-15 carries the first human in space

trurle

Banned
NAA funded a series of Boost-Glide optimization studies beginning in late 1957 and continuing for several years. Initially the '15 was to ride side-saddle on a Navajo booster rocket and fly several thousand miles (Vandenburg to Canaveral). No serious re-entry problems since the aircraft never really exited the atmosphere. The Later studies involved three G-38 boosters (first stage two, second stage one G-38 and third stage the internal fuel in a stretched X-15). The ship could reach LEO but the wing loading was much too high to fly our (1959) low temperature re-entry programs. Even the sub-orbital flights concluded with the probable ejection of the pilot and loss of the aircraft.

Dynasoar
The basic reference on X-15 orbital vehicle program:
http://astronautix.com/x/x-15b.html

From my experience with simulated reentries, practical way for X-15 to survive reentry may be to leave about 0.8km/s of delta-v in internal tanks on reentry. This mean larger mass to orbit, and likely about 6 boosters instead of 3-4.

On reentry, have attack angle about 60 degrees, and apply low thrust to make glide shallower. This way at fuel exhaustion speed drops to about 5km/s horizontal and near-zero vertical, which is much more survivable for spacecraft without heat shield.
 
Highest" had to boost pretty much straight up therefore the final velocity was limited by gravity, the high speed flights had a flatter trajectory for that reason and since the entire program is based on how air-frames handle in the atmosphere at high speed...

That said, mach 5.5 in 1963 is pretty bloody fast!
 
Fastest flight by the X-15 was flight the X-15A-2 which had been lengthened with extra internal and mounting external tanks and hit Mach 6.7 at 102,100ft. Earlier flights had already established the added thermal coating was inadequate, (several were tried) and difficult to apply and remove. Further on the high speed flight there was severe structural damage despite the coating in several critical areas and that does NOT include the damage done by the dummy “scramjet” attached to the rear fin.
http://www.astronautix.com/x/x-15a-2.html
https://theaviationist.com/2017/11/...ft-after-its-record-breaking-mach-6-7-flight/

Also it’s been pointed out that the X-15 experience has lessons for future reusable winged launch vehicles that may NOT sit well with advocates:
http://spaceflighthistory.blogspot.com/2017/11/x-15-lessons-for-reusable-winged.html

Trurle wrote:
The basic reference on X-15 orbital vehicle program:
http://astronautix.com/x/x-15b.html

It’s a start but there are others that give a fuller picture.
https://falsesteps.wordpress.com/2012/09/15/x-15b-shortcut-to-space/
https://static1.squarespace.com/sta...47047446/The+Navaho+Project-+Looking+Back.pdf
https://static1.squarespace.com/sta...90a97f0f623a1/1493536985979/2008-1_Spring.pdf

Note the following has a lot of mistakes. Not surprising given it’s an Air Force magazine but it does have some good illustrations and background information.
https://www.afhistory.org/wp-content/uploads/2008_spring.pdf

And this one tells you why it was unlikely at best as an initial concept:
http://www.astronautix.com/n/navaho.html

From my experience with simulated reentries, practical way for X-15 to survive reentry may be to leave about 0.8km/s of delta-v in internal tanks on reentry. This mean larger mass to orbit, and likely about 6 boosters instead of 3-4.

There were only a few G-26 boosters available and even clustered they could not give the performance needed to reach orbit. That would have taken the still in design G-38 boosters and even THEN the numbers were soft on getting the concept to work. And this was ONLY possible using the very stripped down X-15 which likely would have not been able to survive reentry. To do THAT required a significant redesign and rebuild of the basic X-15 air-frame which increased the mass far beyond any then available launch vehicle.

Studies showed really only the Saturn 1 (first flight 1962) could have put the X-15B into orbit and that required a second stage or the X-15Bs internal propellant.

On reentry, have attack angle about 60 degrees, and apply low thrust to make glide shallower. This way at fuel exhaustion speed drops to about 5km/s horizontal and near-zero vertical, which is much more survivable for spacecraft without heat shield.

Wouldn’t work as the X-15 was restricted to a maximum reentry angle of less than 20 degrees, (https://history.nasa.gov/hyperrev-x15/ch-6.html) due to the lower fin issues but even when removed the vehicle was limited to less than 30 degrees due to the basic design. (One reason they looked into the delta wing configuration but it was found that only a complete re-design would allow removal of the entire lower fin and allow increased angle of attack on entry) And as the Air History magazine article points to it would have had a “heat shield” since to have any chance of working it would have had to be rebuilt to include substantial nickel alloy panels, thorium oxide panels, (yes it would have been slightly radioactive) beryllium oxide panels, columbium and molybdenum coatings, and finally tungsten and Rene 41 sections. In addition the internal structure of steel and titanium would have to be rebuilt using molybdenum structural boxes. And how well this would have worked is questionable since this was based on the assumptions that the initial X-15 structure could handle speeds up to Mach 7 and the later X-15A-2 could handle speeds up to Mach-8, neither of which turned out to be true.

Dynasoar wrote:
NAA funded a series of Boost-Glide optimization studies beginning in late 1957 and continuing for several years.

Following up on that bit the Air Force was also interested in the studies and NAA had hoped to extend the X-15 program to include many of those goals. The problem was the Air Force was less interested in a ‘test’ vehicle than one they could move to an operational status and were not supportive of the NAA work even though they were interested in the possible data.

Initially the '15 was to ride side-saddle on a Navajo booster rocket and fly several thousand miles (Vandenberg to Canaveral).

Really no other way to do it since the G-26/G-38 was only capable of handling load stress from that position. Which would have made clustering them a very “interesting” exercise.

No serious re-entry problems since the aircraft never really exited the atmosphere.

What about aerodynamic heating? In general I’d expect the velocity would be similar to the X-15A-2 speed flights with all that entails but at least there’d be no way to put that stupid dummy scramjet on it. Vandenberg is interesting as it had no Navaho facilities and in fact there weren’t any other than Canaveral and dropping the booster going east is problematical?

Still I have to wonder if that wouldn’t have been worth the effort considering the X-15A-2 never managed to reach its design speed of Mach-7 due to the excess drag of the external tanks and heavy ablative coating. Despite the ‘non-standard’ take off situation even a G-26 boosted X-15 should be able to hit Mach-7 with a Mach-3+ start.

The Later studies involved three G-38 boosters (first stage two, second stage one G-38 and third stage the internal fuel in a stretched X-15). The ship could reach LEO but the wing loading was much too high to fly our (1959) low temperature re-entry programs. Even the sub-orbital flights concluded with the probable ejection of the pilot and loss of the aircraft.

Considering they had to ditch the landing gear to make it work AND add a heavy coat of ablative material to the outside I can understand why it likely wouldn’t have worked. It wasn’t until the total rebuild and redesign was included that the possibility of a successful reentry came around and by that point the “X-15B” was so heavy the already marginal L/D glide ratio was horrible.

The thing is, as stated in several of the links above, the extensive work on the “X-15B” concept actually required severe and deep reconsiderations on the assumptions that were driving the X-20 since it too was based on incorrect and false data.

The X-15 as actually flown was not an appropriate configuration for reentry, though it incorporated nearly everything else required for a LEO vehicle.

It’s that “nearly” that is the kicker though :)

Harrison Storms of NAA who we worked with, ultimately released specs for a delta wing variant which would have been able to develop sufficient lift to follow a relatively low temperature flightpath.

That would be the “X-15A-3” (not to be confused with, as many do, the X-15-3 which was the third X-15 built and which would have been rebuilt into the X-15A-3 had it not crashed and been destroyed) which was to be lengthened and have the delta wings and diamond shaped end-plates added to allow flights up and beyond Mach-8. (Thanks to the every valuable Unwanted Blog, Aerospace Projects Review, mach25 media and Secret Projects: http://up-ship.com/blog/?s=delta+X-15&searchsubmit=, https://www.secretprojects.co.uk/threads/delta-wing-x-15.3723/, http://www.mach25media.com/x15chap13.html) Unfortunately like the X-15A-2 before it that all was based on a set of assumptions that turned out to be less than accurate. They had at least redesigned the external tanks to reduce drag but the idea of it being able to hit Mach-8 off a B-52 launch was in question.

Even this large wing area vehicle would have needed thermal hardening (in this case ablative coatings similar to that actually used later in peak Mach number flights).

More so than was realized at the time since a ‘lifting’ entry doesn’t in fact reduce the thermal loading as thought at the time and likely the design would have needed active cooling to survive even Mach-8 flight.

To summarize, the proposed aircraft-booster combination could have attained a short duration LEO but reentry without extensive modifications would not have succeeded

Very true, in the end the X-15 just wasn’t designed or built to be an orbital vehicle. Oddly the Douglas entry into the X-15 competition, the so-called D-558-III “Skyflash” (so called because it officially was never known as anything but the Model 684) was probably a lot closer to something you could build a very high-speed or orbital space plane from.
http://steeljawscribe.com/2008/01/11/flightdeck-friday-hypersonics-douglas-d-558-iii
http://www.astronautix.com/d/d-558-3.html
https://www.secretprojects.co.uk/threads/douglas-x-planes.3211/
https://www.shapeways.com/product/X4MSHCC6H/douglas-d-684-quot-skyflash-quot-rocketplane-d-558-iii

Randy
 

trurle

Banned
And this was ONLY possible using the very stripped down X-15 which likely would have not been able to survive reentry. To do THAT required a significant redesign and rebuild of the basic X-15 air-frame which increased the mass far beyond any then available launch vehicle.
...
What about aerodynamic heating?
To my experience, having fragile vehicle with lower wing loading is preferable over having high-loaded yet sturdy vehicle at reentry. Critical phase of speed shedding comes actually at 6-7 km/s speeds, with still light structural loads but difficult to manage heat loads, even at reduced-slope powered reentry. Reentry vehicle surviving through that speed range would likely survive to the rest of reentry, because you can effectively control the amount of structural load at max-Q speeds by wings (which have much larger L/D at max-Q speed compared to speed during maximal thermal load)

Considering they had to ditch the landing gear to make it work AND add a heavy coat of ablative material to the outside I can understand why it likely wouldn’t have worked. It wasn’t until the total rebuild and redesign was included that the possibility of a successful reentry came around and by that point the “X-15B” was so heavy the already marginal L/D glide ratio was horrible.
Likely you correct. On place of pilot of hypothetical X-15 in orbital flight, i would not risk (unpowered) landing even if airframe is still perfectly controllable after reentry (which is unlikely due inevitable heavy damage - assuming here the airframe and pilot are still in one piece). Would just press ejection button as soon as speed is subsonic and let engineers work with the wreck.

More so than was realized at the time since a ‘lifting’ entry doesn’t in fact reduce the thermal loading as thought at the time and likely the design would have needed active cooling to survive even Mach-8 flight.
Lifting reentry does not reduce total amount of heat, but allows to make heat pulse longer, therefore more waste heat is re-radiated from the back of wings and final wing temperature is lower. Also, early poly-phenolic ablatives had quite narrow range of effective ablation temperatures (about 2500C), and lifting reentry allows to keep the ablative close to optimal thermal regime for longer, therefore thinner coats are possible. Not sure if knowledge for optimal reentry profile planning was available in time though. Soviets get robust understanding of ablatives behavior only around 1966 (and used it in Soyuz series), after the series of extensive experiments and reentry tests. US may be getting the knowledge at around the same time.
 
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To my experience, having fragile vehicle with lower wing loading is preferable over having high-loaded yet sturdy vehicle at reentry. Critical phase of speed shedding comes actually at 6-7 km/s speeds, with still light structural loads but difficult to manage heat loads, even at reduced-slope powered reentry. Reentry vehicle surviving through that speed range would likely survive to the rest of reentry, because you can effectively control the amount of structural load at max-Q speeds by wings (which have much larger L/D at max-Q speed compared to speed during maximal thermal load)

Yep, that was Len Cormier's (https://en.wikipedia.org/wiki/Len_Cormier) concept with the "Windjammer" and "SpaceVan" light-weight concepts. But I'm going to note it wasn't as straightforward as it seemed and for the X-15B it was not really likely to be all that "light-wieght" even if they could have gotten it down to the suggested 9,900lbs/4,500kg M/T mass. The X-15A-2 was over 17Klbs/7.7kg all-up with ablative coating and all and the ONLY way to get the X-15B in the ballpark was to completely gut the hull and have no on-board propellant, which negated the 'advantage' of supposedly using the X-15 itself. And the natural L/D of the X-15 is still a problem especially higher up. Which is also why the X-15 had issues with high angles of attack in the first place. Pile that on top of the need to completely rebuild the X-15 airframe pretty much from the ground up...


Likely you correct. On place of pilot of hypothetical X-15 in orbital flight, i would not risk (unpowered) landing even if airframe is still perfectly controllable after reentry (which is unlikely due inevitable heavy damage - assuming here the airframe and pilot are still in one piece). Would just press ejection button as soon as speed is subsonic and let engineers work with the wreck.

Well, it's not like you had a choice since there wasn't any landing gear :)

Lifting reentry does not reduce total amount of heat, but allows to make heat pulse longer, therefore more waste heat is re-radiated from the back of wings and final wing temperature is lower. Also, early poly-phenolic ablatives had quite narrow range of effective ablation temperatures (about 2500C), and lifting reentry allows to keep the ablative close to optimal thermal regime for longer, therefore thinner coats are possible. Not sure if knowledge for optimal reentry profile planning was available in time though. Soviets get robust understanding of ablatives behavior only around 1966 (and used it in Soyuz series), after the series of extensive experiments and reentry tests. US may be getting the knowledge at around the same time.

The ASSET and PRIME tests, (http://www.astronautix.com/a/asset.html, http://www.astronautix.com/p/prime.html) tested some of the ablative formulas and worked OK. Though those were on lifting bodies not wing-body vehicles and that makes a big difference. The US did a lot of ablative testing in the 60s and for the most part they can be done but the hope was metallic or ceramic systems would be the better option. Actually the BEST option has always been metallic/ceramic, and active cooling system and a high-heat soak air-frame but as those are expensive, (and there's a real dislike institutionally for active cooling systems) so there is not much preference for them even for a 'reusable' system.

The "spray-on" ablative they tested on the X-15A-2 took over 700 hours to refurbish, was VERY tough to get off and not very effective over 'complex' surfaces like wing-body joints and protrusions. It also didn't wear well and left residue that had to be taken off with a grinder. Really we didn't see any really effective, "easy" to use ablative coatings till the mid-to-late 70s and the issue with use on something like the X-15 is still getting it to evenly ablate on lifting surfaces, (so the lift coefficient doesn't greatly change during reentry) and not getting "hot-spots" on the vehicle. The higher but shorter heat pulse actually is better for ablatives which is why they work for things like capsules and something like Spaceship One.

And none of the ablatives are particularity 'easy' to work with, especially any that can take reentry heating from orbital velocities.

Now on a semi-on-topic aside; The history of the concept, design and building of the X-15 vis-a-vis the X-20 is pretty instructive.

Consider just the issue with mission and parameter changes. As I noted the X-15 originally had more focus on speed in the atmosphere than near-space operations but that was quickly modified before construction began. Especially as only three (3) vehicle were going to be built the large amount of 'hand' crafting that went into them allowed them to be pretty handily modified. And repaired considering how many times they got 'pranged' over almost 200 flights.

The X-20 on the other hand had to be almost perfect the FIRST time from the very start. Not only were the mission parameters pretty unforgiving, (orbital operations are like that after all) but the most basic design considerations were that it was going to be the first of multiple operational vehicles so it was both prototype and primary operational vehicle wrapped up in one. (Those familiar with the Shuttle may find this sounding familiar and there's a reason for that) "Operational" in and of itself means more airframes than a test vehicle, maybe not many more, (see Shuttle) but arguably more and as well they have to NOT be 'hand-crafted' even on an industrial scale.

The problem was the X-20 WAS very much a difficult and complex vehicle even compared to the X-15 and it was shown in the difficulty and expense of the project to the point it was canceled. One can even argue that had it actually BEEN a test vehicle like the X-15 with a limited production run and a defined 'test' program in place it likely would NOT have been canceled!

But that also points out the main issue with a defined test program and a limited number of test vehicles. You don't deal with significant failure well and unless you can replace any loses you WILL eventually run out of airframes or mission goals. NAA kept pushing for more advanced X-15s and while initially there was money and resources to re-build there wasn't enough to build more airframes and eventually even that ran dry as the Apollo Lunar program grew and the 'need' for high speed research took a backseat to the need for more directed and direct applications.

I'd of really liked to see a couple more airframes built and the program extended to higher speeds and altitudes but as noted above it would have taken a great deal of effort and eventually lead to needing what amounts to a 'new" vehicle for the higher end applications. And here's where the X-20 failed since pretty much anything it could do could be done 'cheaper, easier, and faster' using a ballistic capsule. I've seen it often that many consider the X-20 the "optimum" way to get "five astronauts and a couple loafs of bread" to a space station and frankly that's arguably and demonstrably false. Even if we don't include the glaring fact that it never flew.

Mercury was never designed or built to be reusable but it could have been done within the basic design. The same was true of Gemini and Apollo. They never were because there was no need for it, because the main requirement was "soon" rather than anything for sustainability. It is "assumed" that the X-20, being a winged, reusable design would reduce the costs over the ballistic capsule and at first blush that looks true. But only because there was no reusable capsule design data at the time to be used in a counter argument. In fact a much less demanding airframe (X-15 post-program study above) when studied closely shows the majority of the assumptions are on shaky ground to say the least. Especially today when we actually DO have some reusable capsule data for comparison.

In an alternate time-line I'd wish to see the Air Force pull its head out, (trust me, as a career Air Force person "I" guarantee they very much tend to be the type to miss the forest for the trees as an institutional imperative :) ) and realize that no one on the political side is every going to give "space" straight up back to the military as they wished. (As it was they didn't figure this out until the early 80s when "surprise" they finally realized that YES having agreed to use the Shuttle for all spaceflight means those in charge are going to actually MAKE you use the Shuttle! Now who's laughing up their sleeves over those 'annoying' requirements you made NASA agree to meet for your support? Ha!) Hoping on an extended X-15 program that progressed UP to X-20-levels was likely a much smarter choice as it would have allowed incrimental progress that would also be well visible AS progress for the money and effort spent.

For example the idea of using the stored Navajo G-26 boosters, (none of the G-38 were ever completed but it would have not been difficult to re-build some later in the program) to boost the X-15 or X-15A2 into higher performance flights is very interesting. Granted the performance of the G-26 isn't that great, (http://www.astronautix.com/n/navahog-26.html) it boosted the almost 65klb gross mass Navajo missile, (compared to the X-15A-2 gross mass of a bit over 35Klb) to Mach-3 and about 43Kft altitude. Call it putting the X-15A-2 to around Mach-4 and over 50,000ft before the vehicle itself adds somewhere between 1600 and 2000m/s velocity on its internal tanks. (The external tanks really added a lot of stress and drag to the vehicle which is why it couldn't hit the expected Mach-7/8 speeds)

No you don't hit orbit very soon, (or very easy :) ) but it makes a clear progression with very specific lessons learned and data built up. And in doing so you probably don't lose sight of the end goal which is arguably what happened with the Shuttle. (Don't tie all you "requirements" into a single vehicle since quite obviously if you lose it or any capability that comes directly off your overall capability. Again something that should have been a 'lesson-learned from OTL's X-20 since loosing the X-20 didn't materially effect the Titan and the capability could be replaced and/or expanded on demand. The same could not be said of the Shuttle both due to design and due to policy/politics)

Frankly anything above Mach-8 is going to require a full redesign and rebuild of the basic X-15 but that would be a 'logical' progression in this case and quite defensible in a TEST program but not so much in an operational system. This way by the mid-70s if you haven't reached orbit you'll have it in sight.

Randy
 
Ok, not to pummel a recently deceased equine, (he's only MOSTLY dead after all :) ) but the more I look into it the more "interesting" it becomes.

For example I mentioned how "doing the math" it's pretty obvious the Orbital X-15 idea won't work. Well it turns out that comes from not knowing ALL the details. I linked to a online publication of the Spring 2008 "North American Aviation Retirees Bulletin" with an article titled "The Manned Scramble to Orbit" which gave more details from a November 1957 "secret" Technical Summery for an "Advanced X-15 Research Vehicle". (Keep in mind the X-15 didn't actually FLY until June of 1959 while we're about it) Look at it folks, it's a doozy. It's suggested there be a three "step" program with several possible alternative plans.

Step 1 being mounting a 'standard' X-15 on the nose of a "strengthened" G-26 Navaho booster with two more G-26 boosters for a kick start to achieve speeds up to almost Mach-10 (10,850fps) and a range of over 1,000 (1,115 to be exact) miles. (Note this is a 'standard' X-15 which couldn't survive Mach-6 without help) Step 2 rebuilt the X-15 in to the X-15A with "alternate structural materials" to withstand temps up to 1.600F for short periods of time. This was then mounted on to a pair of "parallel" staged G-38 boosters which would propel the vehicle downrange to a distance of 1,741 nautical miles and a top speed of almost Mach-15. The kicker here? Somewhere in that "standard" dimension X-15 body was a bay with several hindered pounds of "photo-reconnaissance" equipment. Wait, what, how...

Take a step back and suddenly that makes a bit more sense overall and yes in fact the article confirms it. While officially the companies of Martin-Bell and Boeing-Vought were slugging it out to win the Dyna-soar contracts NAA was throwing its hat into the ring by trying to slide the X-15 into the match! And mind you this is while NAA was subcontracting to study air-launch and air-breathing launch vehicles for the Boeing-Vought group!
Those sneaky bastards! And well kuddos for it as well as they had big iron bound, brass alloyed ones as you'll see...

Step 3 was the X-15B model with delta wings*, advanced propulsion and air-frame that topped out at over 40,000lbs and to push that mass to speeds in excess of Mach-20 they were going to mount it on a G-38 'second' stage with to G-38 booster rockets to get it all started. Wait that's only one more booster than Step 2 how... Oh, did I forget to mention that the first-stage boosters would burn LOX and a fuel called "Hydyne" (https://en.wikipedia.org/wiki/Hydyne) which was a mixture of "60% unsymmetrical dimethylhydrazine (UDMH) and 40% diethylenetriamine (DETA)" developed by Rocketdyne to improve performance over kerosene. WVB used it in the first stage stretched "Redstone" used to launch Explorer 1. Nasty stuff but hold onto your hat because the second stage had its RP-1/LOX engines with ones capable of burning RP1 and ...FLOX! Even better, remember that "advanced propulsion" system on the X-15B itself? It would mount what was designated by Rocketdyne as an S-4 engine which burned liquid hydrogen and... liquid fluorine for a whopping 75,000lbf thrust at altitude!

Whisky-Tango-Foxtrot over??!!??
(Note if you actually think this is insane or even "out-there" you need to study the period more closely, this was one of the more workable and sane ideas which is why it get so much press but not enough study!)

NAA followed that up with a submission to the Air Force with three broad "plans" to reach these goals.

The "Basic" and "Plan I" used a trio of the above modified G-38 boosters and an X-15B while "Plan II" used the G-26 booster with similar modifications and a modified "standard" X-15. Note that all models and plans included the fact that a "equipment and experiments" bay was included and various reconnaissance systems could be swapped in if desired. So again we see the "obvious" play for the Dyna-soar contract...
(Again, iron-bound, big brass alloy ones my friends)

* A fun bit is this is apparently NOT the delta wing X-15B we tend to think of as noted this was put forward in 1957 and another NAARB issue, (Spring 2011, https://static1.squarespace.com/sta...b2ba7ea02a699/1493537352324/2011-1_Spring.pdf) had an article titled "The Proposed Delta Wing X-15A-3" which shows the NAA proposal for the one we know and love came about in March of 1967 and is based on initial work done in 1963 on a proposed hypersonic test vehicle. (Hence often referred to as the X-15HTV) Obviously it is itself based on the 1957 proposal but the actual study and wind tunnel works seems to date from 1963 to reach the known design. Oddly though it's noted the maximum speed planned was under Mach-8 for the most part though the approach and landing speeds were less than the 'standard' X-15. (345mph for the former and 225mph for the latter) And as per above adding a 'boost' by a Navaho booster would significant increase performance.

Eventually to work with and withstand double digit Mach speeds the "X-15" would have evolve or morph into a more defined form. Despite it being a Lockheed design derived from work by Martin I've always felt that it would have converged on something similar to the L-301/X-24C design:
https://en.wikipedia.org/wiki/Lockheed_L-301
https://crgis.ndc.nasa.gov/crgis/images/d/df/PEN00264.pdf
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19790007769.pdf
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19790008668.pdf

Which is arguably likely given the way hypersonic air frame design evolved anyway:
https://apps.dtic.mil/dtic/tr/fulltext/u2/a242768.pdf

Randy
 
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