F-14D,
"FWIW, only the GD proposal for AIM-152 (AAAM) was podded. Hughes' rocket-ramjet proposal wasn't. Wonder how it would have been mounted had AAAM gone to fruition and USAF actually adopted the system (which they said they wouldn't do). Have heard some speculation that it wouldn't fit in F-22's bay."
The thing about stealth and LRAAM is that they are more positively reinforcing than most might assume, especially over a 'busy' air defense environment like NATO/WARPAC.
The Stealth jet gets reach-in to match it's new AESA lookin, a noted problem for F-15s trying to CAP threat baselanes as Iraqi jets came south to intercept the inbound raid columns was that the 25nm AIM-7 simply didn't have the oomph to hit threats at distances beyond which the 2,000ft shotfloor nominally protected lolo ingressers. Assume that's not an issue for an 'everyone's an indian' condition, 200 miles the other side of the cowboy fence and you still have an aperture lookdown restrictor that inhibits the jet from scoring in-close because the AESA is fixed and likely tilted upwards to keep from hogs nosing any radar that looked up when the radome was fenestrated to dielectric state. A long lance gives you a long E-pole standoff and the radar isn't look-angle scan limited from tracking through to impact because terminals comes about the point where you would be launching a Sparrow.
Now, there was mention of cheek arrays and the like on the F-22 from early on by I honestly don't know if there was space for that (or a proper fuselage inclination angle) on the YF-23 or not.
The Converse is also true, in that a supercruise shooter with some height on him, trying to chase down high value assets like Mainstay and Midas is going to be moving at a pretty good clip. And irrespective of what the pole boost provides, that means he's gonna catch a lot of shots in the teeth from the likes of SA-4/5/10 which, at altitude, have ranges well above 35nm.
Traditionally, this has been why the USAF has 'disregarded the Phoenix shots' as being impractical in a tactical environment. The Phoenix was slow. The AAAM with a relight terminal and a high energy loft from an ATF-23 would be anything but. And the _stealth aspect_ lets you remain essentially wings level and pointed at the target for the entire time of flight on the weapon. So that even if that A-50 is doing pylon turns around an SA-10 site, you can shoot it from as far as your weapons system will reach without worrying about a dozen other, 'minor' SA-2-3-6 threats beneath you.
"I do remember reading that although Northrop didn't talk much about their launching system, they did say it wasn't a trapeze. One other thing noted was that the launch mechanism would be modified for production to avoid the single failure sterilization concern you note."
See, I always thought that the LAU-142 was universal to the ATF program and had been in design all the way back in DemVal. It has an advantage in that, by extending the weapon away from the launcher roof/spindle mount, you can tandem stagger the fins so that total separation as carriage box volumetric numbers are determined by fin:body rather than fin:fin adjacency.
When I hear words like LAU-106A/A (which is basically a stubby ejector for insert into another pylon) and LAU-114 (which is essentially a vanilla Sidewinder analogue rail without the digitals to support a -9X, let alone a dropfire mode) it all brings me to a conclusion that the internals on the YF-23 were not terribly well thought out. And yet that cannot be because internal carriage is essential to both the low-RCS and the high-fast mission function of the entire airframe design. So you know they wouldn't be so careless unless there was a major technical shortcoming inherent to the design which they could not otherwise overcome within the DemVal period.
Of course, maybe the USAF evaluators were just doofuses.
You look at the Boeing PWSC, almost decade later with the (Ex-MDD) Phantom Works once more in the driver's seat on Boeing's ugly duckling and it's clear that the entire JSF DEMVAL downselect is flawed because there is no effective way to compare the tailed delta F-32 to the all-delta X-32. And the X-32's up and away performance -vastly- exceeded that of the X-35 in all areas except carrier approach and STOVL while the Boeing was much easier to manufacture.
Going back to the YF-23, I know I would not want to explain to my board why we thought it was necessary to go from a 13ft structural void to a 24ft equivalent in the middle of our new jet fighter, because we hadn't read the requirements document carefully enough.
And that's where things get interesting in answering your next question.
"Not sure what you mean by, " 'compressed carriage' (aka folding fin)". The compressed carry, to my understanding, was the smaller fins of the AIM-120C which, although not yet publicly revealed, development of which was certainly known to the two teams."
In a traditional rotary launcher, if you fold the fins flat, your principle concern in sizing the bay volume becomes how many weapons you can fit in a given cube of volume around the rotary spindle without touching the sides of the fuselage. The latter in turn having fixed limits as a function of frontal area, area rule and fineness ratio as 'pinch and flow' in fuselage design.
If you want positive control over the weapon all the way through the boundary layer flow field around the lower fuselage, another issue raises it's head however as even the most compact of long-arm rams-
In a world of ever-accelerating change, we move forward faster.
www.exelisinc.com
Adds significantly to the spindle + ejector + missile condition. So much so that you can really only make it workable by biasing the spindle upwards towards the roof of the bay and widening the fuselage to accomodate a grape cluster effect whereby each weapon hangs at an angle below the other other and the rotation of the weapon axis is only sufficient to bring the new missile to vertical -after- the preceding one has left the jet clearing the space.
If you have fixed fins, however small, your rotary launcher is now designed around a presumption of a sterilized central volume and a clearance arc defined by the fuselage sidewalls while your total carriage count of weapons is determined by how far around the art tanget circumference of the spindle each weapon can be placed to ensure that your largest fin span doesn't interfere with the next weapon over (because the weapons are now no longer nestable, fin:body, at all).
Hence your spindle+ejector-arm defines not just the centerline to bay wall limit but the pie slice void of wasted space between weapon bodies defined by the edges-of-fintips not touching (almost as big as another missile body). And this so rapidly swells the belly as to become impossible to integrate within a fighter sized weapons bay enclosure.
Scraping the bay walls is still an issue but the missiles are effectively pushing each other apart as much as the bay is pushing them in, around the width of that spindle, removing the very reason for setting round objects around a round centerpole condition for volumetric efficiency reasons.
If you cannot fold missile fins it may result in a rotary launcher simply being incompatible within a fighter mission fuselage diameter.
For comparison, here is the B-1 CSRL loaded with SRAM-
See how fat that cluster is?
Standard AMRAAM fin span is 21". AMRAAM C/lipped fins are 19". AMRAAM body diamter is 7" by at least 50%. The GD AAAM had a 5" forebody and an 8" booster can. The difference, is fit the folding fins.
Now, there are alternative means to designing a /multiple/ launcher.
One, which I mentioned, is a reverse spindle as a mount for individual rotary collared launch rails which are sufficiently tandemized as to clear missile fins. The first missile is carried, oriented towards the bay opening, launches weapon and with the missile out of the way, the launcher retracts into a compact volumetric box so that the next round can rotate past it.
And then both those launchers can rotate away from vertical baydoor alignment as the missiles cycle in geared rotation around a _fixed_ spindle whose upper index point has suspension blocks of it's own, providing stiffness through a centerline keel as well as through end collars mounted to the weapons bay bulkheads.
Another option would be what I would call a 'hollow rotary' in which there is no spindle but rather the weapons are set in tubes with four point pin collars each end and racked on the walls of a frame matched to the shape of the fuselage. Let's call this a weapons cage. The upper and lower pins in each end of the tube collars provide secure mounting in the cage frame when maneuvering. And a robotic service unit moves on slide rails in each end of the cage, moving up to the roof or across to each sidewall to grab appropriate weapons from the wall racks with rotating docking clamp armatures.
As it docks with each chosen weapon, the clamp inserts it's own pins, cross-axially and the opposed pins in the cage mounts retract as the arm pulls the tube to a single door in the middle of the cage.
Obviously, this will slow firing rates and implies a single-point vulnerability as the weapons cannot reach the bay door opening if the robotic transfer armature fails. However; there are also benefits in that you do not duplicate multiple launcher arm volume/weight penalities. You can move towards a single bay door sized to the appropriate, maximum, weapon clearance envelope, greatly reducing the keel effects of an F-22 type bay mechanism and removing aeroacoustics from the issue almost completely because the missile tube blocks the bay opening until release.
While the entire cage, complete with outer-moldline stealthed, body contour matching skin can be extracted and replaced as a unit, rather like the 30mm ADEN package on a Lightning. Which further means that, when the cage is inplace, it locks with the fuselage and restores maximum rigidity to the fuselage station frames.
Because the tubes are universal, weapons handling inside the bay and ejection clearance through the boundary flow is largely a 'one shape clears all weapons configurations' compatibility condition even as downards canted pitch strakes on the docking collars force the encapsulation tubes away from the jet as the weapons fire through frangile covers at the front.
Whether you have an SRM or a JDAM or an MRM inside then doesn't matter because the wall mount docking racks on the cage walls slide up and down to provide separation indexing relative to the size of the tube and again, only the door has to be big enough for a 'biggest bang you want to drop' condition.
And then we come to this-
Complete Patent Searching Database and Patent Data Analytics Services.
www.freepatentsonline.com
Which incorporates a more standard approach to a rotary launcher as well as some of the features I highlighted above. But importantly, it dense-packs _two_ missiles on single ram ejectors, right next to each other. Why is this critcal?
Because the weapons are doubled they have to eject off of paired (LAU-106A/A) stubs on-mount but when they drop the extending arm solution they cannot be tandem staggered t reduce fin clearances (if they are full finned and not folding). Further, since the patent was filed in 1985 and released to public view in 1987, just about the time the ATF team leads came back and said "Not good enough, we gotta start all over again...", it implies that the discontinuation of the launcher came about because the new configuration would no longer support it.
And last but certainly not least. This launcher configuration is compatible with a rounded upper fuselage sectional profile, was filed, not by Northrop.
But Lockheed.
If I may be permitted a further digression, let's talk about the Lockheed ATF design since so little has been revealed about the YF-23's design history as configurations.
First, here's the Boeing ATF concept submission-
Here is a later iteration-
And here is the Rockwell Missileer-
And here it is as a 'conventional' MRM carriage variant-
And here is the Lockheed ATF-
All big bellied, wide hipped, aircraft designed around a large wing supporting a big internal or external weapons carriage capability equivalent to _LRM_. Bigger than Sparrow. Not an MRM, 60% AIM-7's size/mass.
Here are the Boeing, Lockheed and GD ATFs together-
Whose 'blended' configurations supposedly lead to this-
At which point I have to object and press the BS Alarm button.
Fire alarm whooping and rising x3
www.soundsnap.com
Why? Becasue what is it that all of these jets have in common with each other and -not- the Raptor?
They are long, weak, fuselage torsion body forms with just enough width to fit _one_ internal bay. Not three.
Something that might be indicative of a common solution deriving from a common weapon system/launcher configuration, coming to these companies out of the Black World.
Indeed, if you would believe Lockheed's official historiagraphers, the ATF design shape is essentially an F-117 flipped upside down.
That's wishful thinking based on facet angle reverse symmetries. Look at where the wings are that's what counts, structurally.
Midwing monoplanes have little in common with low or shoulder mounted monoplanes. Does an F-5 share more structural commonalities with an F-15 than an F/A-18?
Humbug.
The Lockheed ATF concept looks like a supersonic F/A-18.
a. It has a vertical or 'differential' area rule allowing a big spine as deep forebody with a
reduced engine area.
b. A long, uninterrupted yet, relatively slender underbelly with waist mounted inlets.
c. It has highly swept fins mounted directly to the fuselage engine nacelles.
d. It has an enormous LEX.
Now look at this-
And what do you see?
1. A sturdy if not chubby box frame fuselage sans discrete nose/engine/empennage
elements.
2. Sidebays on inlet trunking mounted ahead of the main bays, broadenign the shoulders of
the airframe.
3. Shoulder mounted wing leading to minimal differential rule and minimal structural
pathway issues with carry through along the entire corner of the box vs. internal volume
within it (midwing monoplanes have to size their fuselage ring frames to the amount of
torision and compression each individual frame will endure while connected via weak
longerons).
4. Very compressed, almost bodybuilder like squatness of the airframe. 'Powerful, not
Pretty'. It's area rule theory is limited to the extent that the afterbody doesn't exist as
much as reverse-tapers smoothly. It's a delta with integrated Stabs as TEF.
What is wrong with the F/A-18? What has plagued it's midlife decline?
Center barrel cracking due to both carrier landing stresses and the tendency of pilots to abuse it's high AOA capabilities by 'wheelie-ing' into high off angle missile pointing solutions.
What has plagued the early F-22 with possible sabotage from Russian titanium suppliers?
Poor annealing which led to severe cracks in the tailboom mounts.
In 1987, Lockheed's President, Sherm Mullin (sp.) came back from a meeting in which he had been _told_ that the jet wasn't up to snuff. And the skunkworks went into a major overhaul of the configuration, top to bottom, back to front that burned the midnight oil for about 3 months.
During TAC Brawler testing, the principle threat was found to be, not radar but IRST. The point by which turning across the scan arc of a GCI radar brought the attention of fighters was 20-30 miles past the point which a simple lighting of the afterburners would cause the threat to go pointer on it's own.
And yet the USAF wasn't worried about the MiG-23 or 25, both of which could outsprint the F-22 at similar heights, over considerable distances. They were afraid of the Su-27 and MiG-29 which had greater installed T/Wr to the prior generation but in no way to equal (wing sweep as aspect ratio + materials) their high Mach performance.
'All things being equal' as RFLO reduced frontal signatures, sensor wise, what's the difference between the Flogger/Foxbat and the Fulcrum/Flanker?
The earlier fighters have their IRST below a long nose. The other looks up from in front of the canopy.
What's the principle F-22 'last best move' SAM evasion? A 7G pull thru into a split ess that radically changes the intercept geometry by taking the slantrange downhill some 4-5 miles from FL50 at Mach 1.5 or better. Which is at least part of why it's built on a short, rigid, torque box fuselage, not a long, skinny, supersonic area rule superior, one.
i.e. Why it no longer looks like a cubist F/A-18.
Starting in the late 70s, the Syrians played red rover come over games with their MiG-25s looking into Lebanon and northern Israeli territory.
After Bekaa, the Israelis were in no mood for this kind of nonsense and set a trap. Using CH-53s, they heliportaged HAWK SAM to a mountain well north of their established lines, and shot up into the ground track of the Foxbat whizzing by. Whether damaged or simply out of energy and altitude in it's evasion, the MiG-25 was subsequently killed by F-15s (some versions of the story reverse the pusher-impaler roles).
Finally, the Soviets maintain a significant inventory of both long and short burn AA-10 Alamo IR variants with one of the first capabilities to 'ride the beam' of a simple RF uplink through the radar, boresighted to the IRST. This missile is solely associated with the Su-27 and MiG-29.
So what happened?
Something put a squirrel in the USAFs shorts, that's what.
Either a new radar or waveform became available to the Soviets, allowing them to detect the ATF baseline RCS and denying them the deep penetrating high-fast profile.
Or the USAF fighter pilot community decided they wanted more than a niche role, assassinating HVAs (the entire Tom Clancy 'Frisbees of Dreamland' first mission scenario in _RSR_ being a veiled threat if not an honest method indicator of what the ATF was supposed to do) as conventional options to dogfight with. And TAC Brawler supported this via issues with high-cold plume or Mach shock IRST tracking as burner use to change-lane in the 50K supercruise envelope.
Or a significant, blackworld and early LRM package/launcher mechanism hit a major stumbling block and did not eventuate.
With the result that we reverted to another (then) non-existent missile baseline which, because it wasn't really compressed carriage compatible (and never would be, even as the 120C) required a major change in the configuration of the fuselage.
The YF-23, with it's tubular forebody, was not adaptable to this late breaking change and the new, big-span, AMRAAM and the pallet/cradle system they kluged together to make it so was so obviously incompatible with the _mission requirement_ as much as bay design that they have hidden it's adhoc nature from the public for decades of embarrassment since.
IMO, it is highly indicative of the total structural failure of the YF-23 to be adaptive to the changed (?) mission profile that the NATF variant was in fact basically a different airframe that looked like the delta version of the Super Hornet 2000.
At some point, the USAF wrote or rewrote the specification in such a way that SD&M became SC&M and Northrop/MDD failed to pick up on the implications of this or knew it and couldn't do a thing about it because the USAF was demanding that they deconflict weapons on non-functional launchers as single point vulnerabilities which could sterilize the whole weapons bay. And the only answer was to cut an EVEN BIGGER (66-69ft fuselage increase overall, 13->25ft long weapons bay aperture cutouts in same) hole in the belly of their jet, to shift the Sidewinders forward and away from a conventional, pathetic, X3, AIM-120 side-by-side launcher pallet configuration.
The very slender, sleek, lines which makes the Ghost beautiful, also renders it torsionally weak as soon as you cut the longerons around the weapons bays.
Likely rendering the YF-23 'double inferior' as both insufficiently rigid to function as an SC&M platform and insufficiently armed, to be a viable BVR sniper when the AIM-120 is such a mediocre performer due to class limits deriving from it's F-16 compatibility compromise origins.
You will recall I said that explaining to the Northop/MDD board why the YF-23 lost the ATF competition when it was at least .4 Mach Points and 15-20db stealth superior from all aspects would be ugly?
Imagine what it means when the answer is: "The USAF wanted an airplane which could execute minimum 6G breakaway turns after firing a minimum four, discrete launcher redundant, MRM and we couldn't make our airframe both fast and rigid enough to compete because the launcher and/or encapsulate missile system we were relying on, broke in design."
Lockheed dumped their big internal bay design in 1987 by effectively rendering public their rotary launcher patent and going back to the drawing board on the airframe.
By compacting it to a squat pyramidal delta shape, they completely redesigned their weapons system to allow for discrete carriage of AIM-120 across a broad body and they dumped their '10%' as either STOL reversers, supersonic drag penalty or operating weight = fuel margin on a now 60,000lb jet to get sufficient transverse rigidity to support the enormous, hollow, spanwise, void in what became a big, flat, boxframe fuselage with a shoulder not mid mounted wing.
Or as the Russians call it: a Suitcase.
All this so that, even if the jet was detected, it could maneuver under the massive Q loads of supersonic speed sufficient to breakaway into cross track conditions that prevented threat missile shots from making the cutoff across a hypotenuse of changing range as opening range-rates.
"Regarding YF-12 and three missiles, in order to reduce cost for the prototypes they stuck the fire control in one of the bays, leaving only three available. It would have been repackaged for the production F-12B, and what few drawings/illustration we have of that indicate that it could use that bay for a fourth AIM-47, or in some depictions a cannon, which never made that much sense to me."
And I thought 2nm Aphids on the Foxbat was crazy... Maybe it was a death ray.
"All in all, a fascinating post."
Thanks!
