Not exactly a door, but here's a similar rotating assembly (swing out missile arm) that was used on the Boeing X-32. Not just farther from the hinge but also with a full sized 2000lbs bomb...pretty much 5 times the weight of a BVRAAM
View attachment 16872
> I think you misunderstood my sentence. See, in front of a 20-30 ton gross weight, a 200 Kg AAM is just <=1% weight, but when small deflections of control surfaces can maneuver the jet then a civillian like me would definitely think about
dynamics of IWB door & weapon attached to the door.
> I said about the AAM attached to door but
in the X-32 SWB launcher the weapons weight is taken by the structure/holder/launcher above them (outlined in RED below), not the door. And that structure/holder/launcher is supported by swing-out arm (marked in YELLOW) which doesn't seem to be too strong & fast moving. I'm not military historian type fan but IDK if any historical fighter has implemented SWB like this, may be a bomber or attack jet.
>
I can be rusty with PCM & mathematically wrong but i'll put what i understood, let's revise
moment of inertia. For a simple pendulum MoI= (1/2)m.r^2 & for other basic structure we see formulas below.
We see that it is
directly proportional to radius/length, that too power of square
> Hence when a stealth fighter has to
quickly open door, launch & close door, typically happens in 1-2 seconds for single AAM launch, it is not a good idea to attach weapon farther from hinge.
> And if the load is
mixed with heavy JDAM type weapon & the AAM has to be launched 1st then it is very
bad idea to put both on a common swing-out arm in a SWB. It'll take
very long to operate. Check this original video of X-32 still on Youtube :
View: https://www.youtube.com/watch?v=vdRPXJyoqIk
Such
long operating time of IWB/SWB on a stealth fighter is
UNACCEPTABLE
Four launchers that I've used are green and weirdly shaped as compared to the door ones. These are ejector launchers.
The launchers in the door are simple sliding rail launcher as used in wingtips of fighter. When closed, they're disabled (black) and enabled only when the door is opened to its maximum (yellow).
> The vertical heavy duty
ejector launchers like LAU-142 on F-22 & LAU-147 on F-35 are electro-mechanically programmed as per weight of weapon AAM/AGM to literally push/punch them out. I think it is only for central IWB, not SWB.
- For heavier AGM the jet should not bank/maneuver much
- For lighter AAM the bank/maneuvering angle can be higher, may be more than 90 degrees or even upside down perhaps. But the roll, pitch, yaw rates are limited AFAIK to accidentally prevent collision of weapon with the airframe.
> I'm obviously not expert with aerodynamics, so i can't comment if a
rail-launcher is safe to be
attached to IWB/SWB door. If it works safely then why should i have a problem? I just don't know a live example of it.
F-35s have been launching missiles from a similar door based launcher for decades now.
View attachment 16873
> I was about to attach this same pic. We can easily see
how close AIM-120 is to the door hinge. Bcoz this is an extended/portruding hinge, this is as close as possible it can get.
Here's a better closeup pic:
I had this Su-57 diagram in mind, some fan made it to show 6 AAMs future capacity. we see an ejector rather than a rail-launcher. The trajectory does look awkward.
And coincidentally or scientifically by R&D the
F-35 seems to be using similar spring/piston/pneumatic type ejector (LAU-147) as seen in this video :
View: https://www.youtube.com/watch?v=d1VFBUWkOoY
I'm attaching a screenshot in case video gets deleted.
The ejecting angle is closer to vertical compared to Su-57 diagram above & your diagram.
I found a rare pic of LAU-147 launcher on the IWB door. So it is ejector, not a rail launcher.
None of whatever you told happens.
>
Fighter jets with digital FCS are intentionally made unstable. So the FCS, as per atmospheric conditions & maneuver input,
continiously adjusts the control surfaces every fraction of second. This can be noticed even in civil passenger jets which are made stable. Then we are talking about
unstable jets with a big bay door & load attached to door.
And if your counter argument is that these are advanced AMRAAM that can be simply shot out blindly using LOAL, no need to guidance, can compensate...then here's F-22 using is wired ahh trapeze launcher to shoot vanilla LOBL (that required some stabilization) since I don't know how many decades
View attachment 16874
Let it be Vanilla, Butterscotch, Black Current
>
LOAL/LOBL relates to guidance, nothing to do with dynamics of weapons release. Different AAMs have different off-boresight envelope, it depends on jet if it has distribusted RF/EO sensors to guide the AAM outside that seeker envelope, or by other jet.
> F-22's SWB trapeze launcher is LAU-161 which is a rail launcher but is
attached to airframe, not the SWB doors.
When making extraordinary claims (like
all 5th gen uses bi-fold doors) always try to back it up with some extraordinary evidence.
Here's YF-23 without bi-folding doors...just
two huge doors that close one single
large bay
View attachment 16875
>
Nobody here is in any position to make any kind of claim. Let's not use meaningless lines.
> Just bcoz there is a
historical flying example of something doesn't mean it is a right standard, especially when YF-23 lost competition, so we don't have sufficient data either ways to talk on its various aspects compared to any production jet based on active duty, maintenance, upgrades, etc.
> We see
noticeale differences b/w YF-22 & F-22; X-35 & F-35; FC-31 & J-35. Also, the original YF-22 was different that what was made. They told in Discovery Channel 1990s documentary (still there on YT) that they redesigned YF-22 externally in just 3 months b/w July & October 1987. So may be
if YF-23 was selected it may have made some changes too.
> For RCS, if material & RAM are considered same then it is just the difference in surface area. And we can see that the
bay door of YF-23 has larger area than any 5gen jets today.
> Lastly, if it is true that the
center-line also had weapon launcher then both doors would have to be opened to safely launch it, exposing entire bay, that's not good.