Even without the B-70 to put it on, the wikipedia article makes it sound like PYE WACKET was way ahead of the state-of-the-art of defensive missile technology in the early '60s. Why didn't they keep working on it for other platforms? I assume there was a good reason, but I'm a nukes and math nerd, not aerospace, and I'm curious.
Why Was PYE WACKET Canceled?
- Thread starter asnys
- Start date
And I'm someone who wants to know as much as I can assimilate about anything technical, but alas, when I first heard of Pye Wacket, I was able to find very very little on it.
What I want to know most about PW is how the aerodynamics of lenticular shapes work out, because I think maybe we missed a bet in not developing lenticular space capsules. So for me PW was mainly interesting as an illustration of lenticular flight and not so much as a weapons system.
Still if I knew more I'd tell you, even if it was all about weaponry.
Actually you're someone I'd have turned to to find out more about the aerodynamics, on the assumption that you knew all about the weapon system.
Like, maybe you know the origin of the name anyway?
What I want to know most about PW is how the aerodynamics of lenticular shapes work out, because I think maybe we missed a bet in not developing lenticular space capsules. So for me PW was mainly interesting as an illustration of lenticular flight and not so much as a weapons system.
Still if I knew more I'd tell you, even if it was all about weaponry.
Actually you're someone I'd have turned to to find out more about the aerodynamics, on the assumption that you knew all about the weapon system.Like, maybe you know the origin of the name anyway?
There seems to be some disagreement about that. My preferred explanation, from here, is that it was a reference to a witch's cat, "Pyewacket", in the movie Bell, Book, and Candle.
I did a bit of looking on the aerodynamics of lenticular shapes a while ago, managed to find quite a bit of research dating back to the 1960s;
STABILITY AND CONTROL CHARACTERISTICS OF SEVEN LENTICULAR MODELS AT MACH NUMBER 5
FORCE TESTS ON TEN LENTICULAR MODEL CONFIGURATIONS AT MACH NUMBERS 3 AND 5 AND ANGLES OF ATTACK FROM 0 TO 90 DEG
LANDING CHARACTERISTICS OF A LENTICULAR-SHAPED RE-ENTRY VEHICLE
PYE WACKET. LENTICULAR ROCKET FEASIBILITY STUDY
LONGITUDINAL STABILITY AND CONTROL CHARACTERISTICS OF A LENTICULAR MODEL AT MACH NUMBER 8
STATIC LONGITUDINAL STABILITY AND CONTROL CHARACTERISTICS AT MACH NUMBERS OF 2.86 AND 6.02 AND ANGLES OF ATTACK UP TO 95 DEGREES
STABILITY AND CONTROL CHARACTERISTICS OF SEVEN LENTICULAR MODELS AT MACH NUMBER 5
FORCE TESTS ON TEN LENTICULAR MODEL CONFIGURATIONS AT MACH NUMBERS 3 AND 5 AND ANGLES OF ATTACK FROM 0 TO 90 DEG
LANDING CHARACTERISTICS OF A LENTICULAR-SHAPED RE-ENTRY VEHICLE
PYE WACKET. LENTICULAR ROCKET FEASIBILITY STUDY
LONGITUDINAL STABILITY AND CONTROL CHARACTERISTICS OF A LENTICULAR MODEL AT MACH NUMBER 8
STATIC LONGITUDINAL STABILITY AND CONTROL CHARACTERISTICS AT MACH NUMBERS OF 2.86 AND 6.02 AND ANGLES OF ATTACK UP TO 95 DEGREES
PYE WACKET was actually cancelled before the B-70 was reduced to a research program. Performance evaluation had shown that adding the missiles would reduce the range of a B-70 by several hundred miles and reduce height over target by a certain amount. Taken together, these measures increased B-70 vulnerability, and the missiles didn't add enough back to compensate unless Soviet air defences were much more capable than they actually were. Since carrying them would be counterproductive, development of the missile was stopped.
Sadly it seems as I feared, Asnys! You knew a lot more than I did; that single reference of yours provided just for the name has tons more data than I ever found before.
In context, it is clear enough why the specific program to defend B-70s was cancelled. The question of more general interest is, why is this form of shape for high-speed missiles still neglected to this day in favor of traditional sticks with fins?
Of course the engineering of traditional cylindrical bodies with airfoils, of basic need stuck on the tail but also perhaps fringing the front as well, is textbook and low-risk; you can stick a couple Sidewinders or derivatives thereof on the wingtips of most aircraft, or stick echelons of them or other spindle-shaped missiles on pylons below the wings; if one insists on storing them within bays instead (for reasons of aerodynamic cleanliness, or stealth, or both) it is still well-known how to pack them in. To trade them for wedgie pucks is a big risk; your aircraft must be designed differently and it becomes dependent on this alternative form becoming the new standard, or else on a chancy limited supply of very specialized ordinance.
I guess the fact that two major superpowers have never gone head-to-head in a long drawn out war where technical superiority has time to evolve and prevail has a lot to do with it; OTL the many wars actually fought between peer powers have been of second-tier or less nations in local rivalries, each heavily dependent on purchased goods or licensed derivatives of major-power arms manufacturer products. The manufacturers don't want to offer a risky product; the Third World buyers generally can't afford to take big risks, can't afford their own designers and can't manipulate their First or Second world suppliers (counting Russia and China as the purveyors in the latter category) to supply something bizarre for them. And the wars, between India and Pakistan for instance, are generally short; they blow hell out of each other for a few weeks or months and then there is a cease-fire. Long drawn out wars tend to have one nation involved at least beleaguered and desperate therefore in a bad position to develop their own innovations, while the power with the upper hand (as far the world market is concerned anyway) can rest on the laurels of the arms they purchase in some combination of superior quality or quantity,
If we could envision a scenario whereby high-tech peer powers would hack away at each other for years while somehow not escalating to all-out nuclear Armageddon, we might see adoption of these innovative missile planforms.
But consider this--nowadays the USA at any rate has largely let the air-to-air interception mission lapse, on the theory that if any foe that had sufficient capability to lay down serious devastation on a level greater than just making us very angry, they'd invest in ballistic missiles of some kind and range (or conceivably moderately stealthy cruise missiles in large numbers). With BMs there is as yet no very effective defense, so the likelihood that say Russia would attack us with fleets of Bears and Blackjacks dropping gravity bombs seems quaintly remote; if they tried it because it would be a surprise, our response (since our fighters are indeed not very numerous nowadays and not specialized toward the interception mission) would mainly be to retaliate with nuclear missile strikes; the name of the Balance of Terror game is to keep all possible enemies guessing just what level of attack would provoke just what level of retaliation.
So going back to the last generation of aircraft designed when bomber attacks were feared as the main thrust of an enemy (at that time, clearly Soviet) strike, the standard interceptor was the F-102 upgraded to F-106. And the air-to air missile designed for this role was the nuclear-tipped Genie.
Like the original concept for Pye Wacket the Genie missile was intended to zap an opposing craft with a nuclear blast--unlike PW it would be no tiny blast, although it too relied on "dudding" the enemy weapon or weapons with the neutron flux--if that is, the missile shot were not close enough to blow the incoming bomber right out of the sky.
But to get that close, or anyway enough to ruin the bombs, it did not rely on any sort of fancy maneuvering. It just had a powerful rocket engine and flew straight in whatever direction it was pointed when fired. There was sophisticated aiming involved; the F-106 aircraft's avionics suite, assisted by the continental SAGE system, sought to optimize the aim of the pilot, and it was the intercept control system that chose the actual moment the rocket fired.
Once fired though, the lack of further inputs except a proximity fuse into the direction it went was considered a virtue; it could not be confused, diverted or spoofed; it would just zoom at very high speed toward the target and nuke it.
Now this is one proposition against a turboprop powered Bear bomber, and perhaps something else against a swing-wing, supersonic capable Blackjack; the latter might have enough dodge in it to "get out of Dodge" as it were and waste one thermonuclear tipped warhead. (The F-106 would of course have one and one only Genie in its weapon bay, and nothing else there but that one shot should the Genie be loaded; there would be no room for more missiles nor the retrofitted Vulcan machine gun. The alternate missiles were Falcons which the pilots had little confidence in anyway). Can a one sure fast shot strategy work against another aircraft as fast and agile as the interceptor carrying the missile? I'd say, sure, if the missile has the right combination of high speed and high blast. If we can pack enough thrust into it without flattening the bomb nor blowtorching the interceptor that launched it with back-blast, the same old strategy of "aim the plane, fire the missile, turn!" should work.
Such methods do not require the fancy swerving the PW shape can deliver, obviously. Supposing instead we've reached the limits of thrust and the target will indeed have time to react, and start jinking and with enough range of motion to get out of the effects radii, then there would be nothing for it but to try to match its moves, and here is where superior lift-drag ratios come in handy. Assuming that is, that its guidance system is a match for enemy tricks and it can hold its target lock.
The original concept for PW was that it would have a "dudding" nuclear bomb, but quite obviously one of considerably less kilotonnage than the Genie. But the designers evolved it to a smaller packet still, that would not be nuclear and would have to make actual contact to be effective. The concept of the circular packet can be extended in either direction, to make small missiles (that pack relatively little punch) or big ones that might serve with either HE or nuclear warheads not only for air-to-air but to strike at surface targets. But to carry a big punch, the disk must be correspondingly bigger. Overall a PW type package would be fairly compact, but I'd foresee problems trying to carry them on the smaller planes that tend to be the mainstays of actual combat nowadays. Whenever the USA does use big bombers, such as B-52s, B-1 or Stealth bombers, it is in combat against foes with relatively little sophistication; only these big airframes can carry such alternate missiles. I suppose if PW type missiles became the norm, new designs of fighter/attack planes could develop drum-shaped weapons bays, stacking missiles like chips and dispensing them much as PW would be from the B-70; maybe slide some into bays within the wings. The point is the planes would be a different design than those we now have that assume long skinny missiles, which can either fly mounted on wings and other exterior hard points, or fit within long skinny bays oriented along the fuselage.
Employment of the alternate shape implies that the missile will have to be expected to do some fancy flying; it makes a sophisticated guidance system essential, and is participating in an escalating electronic warfare arms race. This implies it is going up against peer rivals; if two such nations get into a serious and extended conflict they might find themselves forced to develop such options--except that if they are really serious, the war would tend to be over long before the opposing design teams can sketch their visions of highly maneuverable missiles, much less cut metal and get them operational. If the rivals are small though sophisticated nations--let's say apartheid era South Africa versus India, for instance--the superpowers are liable to intervene to damp down the conflict. If the rivals are in fact the superpowers, and it isn't some proxy war but a direct confrontation, with all the potential those would have to spiral right out of control--it might not be long before each is employing everything they've got against the other, and given the nature of superpower arsenals...the next design iteration would probably involve shamans hunkered down in deep caves by torch light, holding flint knapped models tied to sticks and chanting "Zoom Zoom Boom Bang!" Sophistication in this Voodoo Race would involve anointing shamans with mutated extra limbs or third eyes...
I don't know, I have to agree that one would think someone somewhere would have followed through and found a niche for such maneuverable missile systems for some application. SAMs for instance--the targets are jinking all over the sky, and guidance can come from the ground via laser data link that the invading planes might not be able to Wild Weasel very effectively if the beam is tight with no stray side beams. If not General Dynamics or Lock-Mart, Sukhoi or Dassault or Saab. If my speculations don't bracket the target pretty well and I admit they are just rambling guesses, then I really can't say why.
Looking at that article of yours though, which I much appreciated the chance of seeing, I have to say I think I object to the term "lenticular" applied to PW--what we have here is pretty much the shape we'd get by taking a true lenticular solid and a circular cookie cutter, of radius a bit over half that of the lenticular mold, and cutting out a piece with the cutter just tangent to the edge of the form. It is more of a hockey puck with a honed edge.
Like a lenticular form it is bilaterally symmetrical reflected in the plane the circle lies in; unlike such a form it is not radially symmetrical. The wedge shape of the vertical cross section seems to be of the essence.
And it is fine for a missile, but I don't think I like the suggestion of a PW shape based crewed space capsule. This is a matter of the layout the shape makes available; all the space is crowded to the back; you'd have engines competing for that premium volume with crew spaces. I can't envision how it achieves aerodynamic balance in any speed range; supersonic and hypersonic lift tends to derive from pressures evenly along the bottom surface from shock wave pressure and that puts the center of lift at the dead center of the circle; I don't see why it doesn't flip over. I suspect brute force from the propulsion and maneuvering rockets is the answer.
At subsonic speeds the lift shifts forward toward the leading edge and everything seems even worse; also, sharp leading edges are not so great at those speeds and a blunt trailing edge, especially one with a sharp cutoff, would be murderously draggy I'd think.
A proper lenticular shape with radial symmetry seems to be the ticket for a space capsule, manned or otherwise; there is ample volume in the center and the form would have good zero-G orientation ability, with thrusters near the periphery. At hypersonic reentry, Kehlet claimed, probably accurately, that the form is efficient in terms of minimizing thermal protection mass needed, presumably because the bottom surface is rather wider than traditional capsules would be hence lower forces hence heat flux per square unit of area, whereas the upper half is well inside the shock cone for the most part. Lenticular capsule proposals I've seen extend the heavy bottom TPS over the leading edge to a bit of the top there, but have lighter TPS over most of the top--as long as one avoids flipping, presumably in part by concentrating dense masses (including the TPS itself of course) toward the bottom, it looks good. And some Apollo capsule design lenticular proposals claimed remarkably high hypersonic L/D, approaching or exceeding a factor of 4, pretty near what I'm told is the theoretical limit in fact. At supersonic speeds the rounded leading edge would be draggy but lift remains centered on the center of mass. At subsonic speeds this changes of course, which is why Kehlet had conformal wings like a beetle's wing case rising up then, in the back. A cruder method would be to deploy a parasail or even ribbon parachute to balance the lift; it would be draggy but the goal is after all to land!
As far as other sources I've read indicate, the downfall of the prospects for lenticular Apollo CMs was its squirrely behavior on landing on water; tests indicted the form would very likely flip over then. Kehlet wanted it to come down on land, and claimed the shape would simply skid over a solid runway and come to a rocking halt. Well unfortunately most of the Earth is covered by oceans and even if a runway or salt flat or farmer's field is the preferred ditch site, an emergency would have the thing come down at a more or less random location--odds are, that location would be covered in water. Too bad about the flipping then, because the shape makes a perfectly good raft!
I guess if someone make lenticular spacecraft, they'd need a system like Soyuz, TPS or the Dragon capsule for terminal landing--parachutes and retro-rockets that kill the forward momentum while braking the final fall, so it comes down straight and gentle onto whatever surface it finds.
Anyway I don't think I can properly envision what a Pye Wacket wedge shape would do as it fell below sonic speed, and then approached either a solid or liquid landing surface. I can't imagine it would be a very satisfactory raft, with its leading edge sticking up and trailing edge tending to be submerged.
In context, it is clear enough why the specific program to defend B-70s was cancelled. The question of more general interest is, why is this form of shape for high-speed missiles still neglected to this day in favor of traditional sticks with fins?
Of course the engineering of traditional cylindrical bodies with airfoils, of basic need stuck on the tail but also perhaps fringing the front as well, is textbook and low-risk; you can stick a couple Sidewinders or derivatives thereof on the wingtips of most aircraft, or stick echelons of them or other spindle-shaped missiles on pylons below the wings; if one insists on storing them within bays instead (for reasons of aerodynamic cleanliness, or stealth, or both) it is still well-known how to pack them in. To trade them for wedgie pucks is a big risk; your aircraft must be designed differently and it becomes dependent on this alternative form becoming the new standard, or else on a chancy limited supply of very specialized ordinance.
I guess the fact that two major superpowers have never gone head-to-head in a long drawn out war where technical superiority has time to evolve and prevail has a lot to do with it; OTL the many wars actually fought between peer powers have been of second-tier or less nations in local rivalries, each heavily dependent on purchased goods or licensed derivatives of major-power arms manufacturer products. The manufacturers don't want to offer a risky product; the Third World buyers generally can't afford to take big risks, can't afford their own designers and can't manipulate their First or Second world suppliers (counting Russia and China as the purveyors in the latter category) to supply something bizarre for them. And the wars, between India and Pakistan for instance, are generally short; they blow hell out of each other for a few weeks or months and then there is a cease-fire. Long drawn out wars tend to have one nation involved at least beleaguered and desperate therefore in a bad position to develop their own innovations, while the power with the upper hand (as far the world market is concerned anyway) can rest on the laurels of the arms they purchase in some combination of superior quality or quantity,
If we could envision a scenario whereby high-tech peer powers would hack away at each other for years while somehow not escalating to all-out nuclear Armageddon, we might see adoption of these innovative missile planforms.
But consider this--nowadays the USA at any rate has largely let the air-to-air interception mission lapse, on the theory that if any foe that had sufficient capability to lay down serious devastation on a level greater than just making us very angry, they'd invest in ballistic missiles of some kind and range (or conceivably moderately stealthy cruise missiles in large numbers). With BMs there is as yet no very effective defense, so the likelihood that say Russia would attack us with fleets of Bears and Blackjacks dropping gravity bombs seems quaintly remote; if they tried it because it would be a surprise, our response (since our fighters are indeed not very numerous nowadays and not specialized toward the interception mission) would mainly be to retaliate with nuclear missile strikes; the name of the Balance of Terror game is to keep all possible enemies guessing just what level of attack would provoke just what level of retaliation.
So going back to the last generation of aircraft designed when bomber attacks were feared as the main thrust of an enemy (at that time, clearly Soviet) strike, the standard interceptor was the F-102 upgraded to F-106. And the air-to air missile designed for this role was the nuclear-tipped Genie.
Like the original concept for Pye Wacket the Genie missile was intended to zap an opposing craft with a nuclear blast--unlike PW it would be no tiny blast, although it too relied on "dudding" the enemy weapon or weapons with the neutron flux--if that is, the missile shot were not close enough to blow the incoming bomber right out of the sky.
But to get that close, or anyway enough to ruin the bombs, it did not rely on any sort of fancy maneuvering. It just had a powerful rocket engine and flew straight in whatever direction it was pointed when fired. There was sophisticated aiming involved; the F-106 aircraft's avionics suite, assisted by the continental SAGE system, sought to optimize the aim of the pilot, and it was the intercept control system that chose the actual moment the rocket fired.
Once fired though, the lack of further inputs except a proximity fuse into the direction it went was considered a virtue; it could not be confused, diverted or spoofed; it would just zoom at very high speed toward the target and nuke it.
Now this is one proposition against a turboprop powered Bear bomber, and perhaps something else against a swing-wing, supersonic capable Blackjack; the latter might have enough dodge in it to "get out of Dodge" as it were and waste one thermonuclear tipped warhead. (The F-106 would of course have one and one only Genie in its weapon bay, and nothing else there but that one shot should the Genie be loaded; there would be no room for more missiles nor the retrofitted Vulcan machine gun. The alternate missiles were Falcons which the pilots had little confidence in anyway). Can a one sure fast shot strategy work against another aircraft as fast and agile as the interceptor carrying the missile? I'd say, sure, if the missile has the right combination of high speed and high blast. If we can pack enough thrust into it without flattening the bomb nor blowtorching the interceptor that launched it with back-blast, the same old strategy of "aim the plane, fire the missile, turn!" should work.
Such methods do not require the fancy swerving the PW shape can deliver, obviously. Supposing instead we've reached the limits of thrust and the target will indeed have time to react, and start jinking and with enough range of motion to get out of the effects radii, then there would be nothing for it but to try to match its moves, and here is where superior lift-drag ratios come in handy. Assuming that is, that its guidance system is a match for enemy tricks and it can hold its target lock.
The original concept for PW was that it would have a "dudding" nuclear bomb, but quite obviously one of considerably less kilotonnage than the Genie. But the designers evolved it to a smaller packet still, that would not be nuclear and would have to make actual contact to be effective. The concept of the circular packet can be extended in either direction, to make small missiles (that pack relatively little punch) or big ones that might serve with either HE or nuclear warheads not only for air-to-air but to strike at surface targets. But to carry a big punch, the disk must be correspondingly bigger. Overall a PW type package would be fairly compact, but I'd foresee problems trying to carry them on the smaller planes that tend to be the mainstays of actual combat nowadays. Whenever the USA does use big bombers, such as B-52s, B-1 or Stealth bombers, it is in combat against foes with relatively little sophistication; only these big airframes can carry such alternate missiles. I suppose if PW type missiles became the norm, new designs of fighter/attack planes could develop drum-shaped weapons bays, stacking missiles like chips and dispensing them much as PW would be from the B-70; maybe slide some into bays within the wings. The point is the planes would be a different design than those we now have that assume long skinny missiles, which can either fly mounted on wings and other exterior hard points, or fit within long skinny bays oriented along the fuselage.
Employment of the alternate shape implies that the missile will have to be expected to do some fancy flying; it makes a sophisticated guidance system essential, and is participating in an escalating electronic warfare arms race. This implies it is going up against peer rivals; if two such nations get into a serious and extended conflict they might find themselves forced to develop such options--except that if they are really serious, the war would tend to be over long before the opposing design teams can sketch their visions of highly maneuverable missiles, much less cut metal and get them operational. If the rivals are small though sophisticated nations--let's say apartheid era South Africa versus India, for instance--the superpowers are liable to intervene to damp down the conflict. If the rivals are in fact the superpowers, and it isn't some proxy war but a direct confrontation, with all the potential those would have to spiral right out of control--it might not be long before each is employing everything they've got against the other, and given the nature of superpower arsenals...the next design iteration would probably involve shamans hunkered down in deep caves by torch light, holding flint knapped models tied to sticks and chanting "Zoom Zoom Boom Bang!" Sophistication in this Voodoo Race would involve anointing shamans with mutated extra limbs or third eyes...
I don't know, I have to agree that one would think someone somewhere would have followed through and found a niche for such maneuverable missile systems for some application. SAMs for instance--the targets are jinking all over the sky, and guidance can come from the ground via laser data link that the invading planes might not be able to Wild Weasel very effectively if the beam is tight with no stray side beams. If not General Dynamics or Lock-Mart, Sukhoi or Dassault or Saab. If my speculations don't bracket the target pretty well and I admit they are just rambling guesses, then I really can't say why.
Looking at that article of yours though, which I much appreciated the chance of seeing, I have to say I think I object to the term "lenticular" applied to PW--what we have here is pretty much the shape we'd get by taking a true lenticular solid and a circular cookie cutter, of radius a bit over half that of the lenticular mold, and cutting out a piece with the cutter just tangent to the edge of the form. It is more of a hockey puck with a honed edge.
Like a lenticular form it is bilaterally symmetrical reflected in the plane the circle lies in; unlike such a form it is not radially symmetrical. The wedge shape of the vertical cross section seems to be of the essence.
And it is fine for a missile, but I don't think I like the suggestion of a PW shape based crewed space capsule. This is a matter of the layout the shape makes available; all the space is crowded to the back; you'd have engines competing for that premium volume with crew spaces. I can't envision how it achieves aerodynamic balance in any speed range; supersonic and hypersonic lift tends to derive from pressures evenly along the bottom surface from shock wave pressure and that puts the center of lift at the dead center of the circle; I don't see why it doesn't flip over. I suspect brute force from the propulsion and maneuvering rockets is the answer.
At subsonic speeds the lift shifts forward toward the leading edge and everything seems even worse; also, sharp leading edges are not so great at those speeds and a blunt trailing edge, especially one with a sharp cutoff, would be murderously draggy I'd think.
A proper lenticular shape with radial symmetry seems to be the ticket for a space capsule, manned or otherwise; there is ample volume in the center and the form would have good zero-G orientation ability, with thrusters near the periphery. At hypersonic reentry, Kehlet claimed, probably accurately, that the form is efficient in terms of minimizing thermal protection mass needed, presumably because the bottom surface is rather wider than traditional capsules would be hence lower forces hence heat flux per square unit of area, whereas the upper half is well inside the shock cone for the most part. Lenticular capsule proposals I've seen extend the heavy bottom TPS over the leading edge to a bit of the top there, but have lighter TPS over most of the top--as long as one avoids flipping, presumably in part by concentrating dense masses (including the TPS itself of course) toward the bottom, it looks good. And some Apollo capsule design lenticular proposals claimed remarkably high hypersonic L/D, approaching or exceeding a factor of 4, pretty near what I'm told is the theoretical limit in fact. At supersonic speeds the rounded leading edge would be draggy but lift remains centered on the center of mass. At subsonic speeds this changes of course, which is why Kehlet had conformal wings like a beetle's wing case rising up then, in the back. A cruder method would be to deploy a parasail or even ribbon parachute to balance the lift; it would be draggy but the goal is after all to land!
As far as other sources I've read indicate, the downfall of the prospects for lenticular Apollo CMs was its squirrely behavior on landing on water; tests indicted the form would very likely flip over then. Kehlet wanted it to come down on land, and claimed the shape would simply skid over a solid runway and come to a rocking halt. Well unfortunately most of the Earth is covered by oceans and even if a runway or salt flat or farmer's field is the preferred ditch site, an emergency would have the thing come down at a more or less random location--odds are, that location would be covered in water. Too bad about the flipping then, because the shape makes a perfectly good raft!
I guess if someone make lenticular spacecraft, they'd need a system like Soyuz, TPS or the Dragon capsule for terminal landing--parachutes and retro-rockets that kill the forward momentum while braking the final fall, so it comes down straight and gentle onto whatever surface it finds.
Anyway I don't think I can properly envision what a Pye Wacket wedge shape would do as it fell below sonic speed, and then approached either a solid or liquid landing surface. I can't imagine it would be a very satisfactory raft, with its leading edge sticking up and trailing edge tending to be submerged.
Do you have a source for that? All of the other sources I've found say they don't know when PYE WACKET was cancelled.
Either way, though, it still leaves open the question: why not shift PYE WACKET from B-70 self-defense to a research program into lenticular missiles for other roles?
Still, as you say, I would think there would have been investigative research into this at least, even if not a full procurement program.
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Posting from memory, but the source was Jenkins & Landis's Valkyrie: North American's Mach 3 Superbomber. It may be that I've got the details mixed up.
Okay, I've got hold of Jenkins & Landis. If I'm understanding J&L correctly, PYE WACKET was early dropped as a formal part of the B-70 program, but remained active as a separate research project that would likely end up mounted on the B-70:
The Phase I contract was awarded June 1959, so this took place after that. Unfortunately, J&L doesn't have any information on why it was cancelled:
They do mention they were having trouble designing adequate maneuvering thrusters that could fit in the available space; maybe that was part of the reason? They also mention interest in using a PYE WACKET derivative as an air-to-surface missile, perhaps for hitting SAM sites and the like.
Jenkins & Landis said:
The Phase I contract was awarded June 1959, so this took place after that. Unfortunately, J&L doesn't have any information on why it was cancelled:
Jenkins & Landis said:
They do mention they were having trouble designing adequate maneuvering thrusters that could fit in the available space; maybe that was part of the reason? They also mention interest in using a PYE WACKET derivative as an air-to-surface missile, perhaps for hitting SAM sites and the like.
Simple answer is that the Lenticular (damn auto-correct keeps wanting to change that to something VERY not appropriate to this thread) design doesn't "fit" on the standard rail-launchers that are fitted to all combat aircraft. Pyewacket etc would have had to have a specifically designed launch system. Though it could very well have been a cylindrical "dispenser" mounted on a standard pylon if you think about it.
Main problem was it was one of the systems caught up in the general cancellation of advanced projects so never got even as far as a test article so the majority of its actual versus possible benefits were never proven.
"Long/skinny" in a rectangular container "stacks" better as well. From experience that's a major issue at times
Actually air-intercept and domination is still very much the driver behind fighter design. We have fewer aircraft because they are so much more expensive per aircraft and (in theory at least if not in fact, though it would seem the "theory" is correct given test results and past combat) each aircraft is more capable per unit.
Falcon missile actually as the Genie and other "anti-massive-bomber-formations" weapons were designed to fight WWII air battles and not nuclear war air battles where sending more than one bomber to a target was a serious waste of resources.
The "dudding" effect seems to have been over-stated as well as over-used IMO. The design specs for the Genie (as well as the nuclear warheads for various air-defense missile applications) was specifically stated to counter "massive bomber formations" and though not mentioned in weapons systems specifications it was well know in targeting and tracking circles that "friendly" nukes would degrade acquisition and tracking ability, probably more than it would "dud" enemy bombs. Once you started to enhance the radiation output of the weapon you were more likely to kill the crew rather than the weapons themselves anyway.
IR Falcon was always a bit iffy anyway as you needed to see the "aft" aspect of an engine to have enough heat for a lock. Since if you were "behind" the bomber it meant it would be 'past' you and heading inbound this wasn't a very good solution hence the Radar Falcons which had a lot more capability.
Thing is anti-interceptor nukes made more sense than anti-bomber nukes since the interceptor HAD to close on the bomber where as the bomber could (and was expected to) vector away from an intercept as long as it was still proceeding to target. (Point defense doesn't make a lot of sense in the nuclear age unless you're intercepting the warhead itself in a last ditch effort. Which is why defense has always been viewed as a "layered" concept with interception of the delivery system taking place as far away from the target as possible)
PW was initially conceived and designed to overcome the inability of missiles at the time to shoot "off-bore" by having a design that could in fact be "faced" to any direction on launch. Hence you could point and shoot where as a "standard" missile shape would need to follow a more complex and difficult "aerodynamic" path to turn towards the target. While an interceptor doesn't have this "issue" a bomber and some other missions (ground attack was mentioned often) would benefit greatly from such an "off-bore" capability. Of course an aircraft in a tight air-to-air battle could (again in theory) have a significant advantage with a missile that can fire into all aspects of its envelope
(Firefox anyone? )In anti-aircraft combat getting "close" counts for most effective 'kills' rather than direct contact. Aircraft just aren't that "tough" compared to most vehicles. Between high-fragmentation and things like continuous-rod (https://en.wikipedia.org/wiki/Continuous-rod_warhead) warheads you can generate a combat "kill" in most cases within several dozen yards of actually hitting the target. Nukes would be pretty much guaranteed to "kill" an interceptor in several dozen ways from knocking out the radar, blinding the pilot, air/blast/pressure-wave to killing the aircraft with enhanced radiation. The problem is always that your exposing your launching aircraft to the same conditions in most cases as well. This is a problem
Anti-aircraft warheads usually are different than surface target warheads BECAUSE aircraft are so much easier to kill. An air-to-air warhead in most cases will be capable of taking out a relatively "soft" target like a vehicle but not something like a tank or APC. Meanwhile any structure with a minimum of "hardening" (sand-bagged walls and roof for example) would probably shrug off anything but a direct hit with an anti-air warhead. Shaped/self-forging charges of a large enough HE charges are needed to defeat any type of hardened combat vehicle which an aircraft is usually NOT.
In most cases yes but I could see an anti-air PW that had a shell designed to disintegrate into an effective high-velocity splinter cloud similar to the what the Patriot missile does.
Biggest problem would be for "efficient" storage you'd see them stacked "horizontally" which means they would generate and be subject to the highest drag and aerodynamic forces on them at launch. (Stack of poker chips on their "sides" if you will) Or less efficiently but more effective multiple "stacks" inside a aerodynamic form but that brings up weight-and-balance issues as the individual missiles are released.
Down-side is it would take a lot of advances to make such a multi-missile system work as in most cases until very recently you had to expose the missiles own sensors to "acquire" a target unless it was something like an anti-radiation homing missile.
The idea of an attack aircraft being able to dispense a large number of omni-directional missiles in one "pass" was mentioned in the cited article and really if you have some way of "illuminating" multiple targets tossing out a dozen missiles in different directions greatly increases your chances of hits/kills. (Can't find it right now but we have an anti-tank munition that deploys multiple self-forging penetrators which is a similar idea but imagine it over a much wider area. Bonus that SFP warheads would "fit" a lenticular missile better)
Again though your issue is "dispensing" them efficiently.
"Required" due to the need for exhaust and maneuver propulsion systems. BTW on the design based on "PW" have you all heard of "Darque Sol?"
http://rocketdungeon.blogspot.com/2009/05/lenticular-rockets-fgg-3darque-solpye.html
http://www.rimworld.com/dsp/darquesol.html
It was a PW inspired amateur rocket project that flew quite well from what I understand.
The key to subsonic fight is the "deploy-able" lifting surfaces aka: wings and fins which truthfully ALL lenticular vehicles needed at subsonic speeds for stability. The PW derived spacecraft just took to an extreme
*Hypersonic L/D of 4 was shown in testing to be possible with some designs. Having said that though the same testing showed the GE "improved" LRV (http://www.astronautix.com/craft/apollor3.htm) which was supposed to "resolve" certain "assumed" inefficiencies in the original Kehlet design actually was MUCH worse. L/D was horrible and heating models showed it would burn up on entry!
"Flipping"? More like bouncing all over the place in the slightest waves
Can't find the test films on YouTube ATM but the water ones are quite "sporty" indeed
Landing by the way was proposed to just go ahead and land on the heat shield as the "skid-out" was quite stable and gentle under most conditions. You'd have to remove and replace the heat-shield itself but designed right it was a workable system. Water landings however were a problem and would require parachutes for sure!
file:///C:/Users/Campbell/Downloads/AD0263072.pdf
You'd have needed a "Soyuz" like layout anyway since there wasn't THAT much room in the basic LRV layout for extended use. And even so aborts would be an issue unless you "stacked" the LRV on-top of some type of service module. The basic idea was NOT to induce to many aerodynamic issues with a lifting manned return vehicle in the basic Kehlet proposal where as Pyewacket version would have had some issues from the layout. (Though to be honest the aerodynamic covers of the "IK" vehicles and the flat end of the PW based craft would have had better places to put the abort system than a "standard" LRV. Georgia Tech proposed an LRV for a Falcon-5 based Space Tourism Vehicle concept which I also can't find ATM)
Randy