F-35A at Red Flag 19-1

[Gums]

Salute!

Good points about the gun, Spud.

Back in the day when the Hawg was envisioned we liked loittsa rounds. We had slow rates but used more barrels, witness the P-47.

By the early 50's we got to the cannons like the Hun had, and rotating breeches that resembled the old Colt 45 revolvers of western lore and used the same barrel for every shot. And then somebody thot of the gatling gun and off to the races.

As we moved from very close air support and "staying time", the need for a thousand rounds diminished. For A2A we got better sights and couldn't afford to stay around spraying and praying until we got hits.

Best thing nowadays is to be able to select rounds per trigger squeeze. Better yet, to also be able to squeeze again within a second or two like the old guns did in WW2 and Korea. The GAU-8 can do this, but I don't know about the new gun- GAU-22

Gums sends...

[mixelflick]

With respect to the gun, I understand what you're saying. It's good the F-35A includes an internal, though it has modest ammunition (180 rounds?) vs. previous US fighters. Now, when we get to the gun pod on the B and C... I sincerely hope it's not like the centerline pod we deployed on F-4's in Vietnam. Have read nothing but problems with that weapon.

I assume (bad, I know) it doesn't significantly degrade its stealth (or maneuverability) properties. I know there were issues too, but last I knew these were being corrected. Going forward, it'll be very interesting to see how often the B and C carry it. And if Israel gets the B, that'll be a real test.

Mixel, I started the The GAU-22/A thread just to document the F-35 gun system, and address questions such as yours. Check it out if you have not already -- 8 pages of BRRRRRTTT goodness. That thread compares the F-35 with the GAU-22/A gun to other contemporary aircraft and shows the Lightning to have the highest throw weight (mass) per second, the highest rate of fire (compared to non-US aircraft), and a comparable total throw weight compared to older 4th gen aircraft. While at first glance, 180 rounds may sound modest, Dragon documented burst lengths as short as 12 rounds per burst (viewtopic.php?p=405906#p405906). We already know from test flights that the aircraft can fire 60 and 100 round bursts should the occasion warrant. Since the GAU-22/A is reverse clearing, not a single one of those 180 rounds is wasted. This burst length precision means a Lightning driver can opt for upwards of 15 shots per sortie, or hose down an area, or maximize the hit probability in an air-to-air scenario as (s)he sees fit. IMO, this is a capability unprecedented in modern aerial gunnery.

While DOT&E has harped on some gun shortcomings on the -A model, the Killer Bee and C Dragon are meeting all contractual gun requirements. As soon as LM sorts out the alignment issues on the -A, I have no doubt that the GAU-22/A will be one of the most, if not the most, capable gun systems on any aircraft flying today.

Crews has already commented that the USMC never flies the AV-8B on combat sorties without the gun system, and he did not see that changing with the Killer Bee. What the nasal radiators choose to do... I dunno. I'll hazard a guess the flying squids will make a determination on an as mission basis.

I recall comments by JohnWill or possibly others discussing the fact that the mounting system of the external gun pod on the Killer Bee and C Dragon models is NOT comparable to the manner in which the old Vulcan was mounted on the Phantoms, and, as such, the gun pod on the Lightnings should not suffer from any issues that were experienced on the F-4.

We all know how the Israeli's love the gun, and I can't recall a time when they flew fighters without one...

You write this sentence in a manner that seems to suggest the Israeli's love the gun more than fighter pilot's from other nations. Would you care to elaborate on this point? I'm not sure what you mean by it.

First, thank you for your most informative reply re: the GAU-22/25mm. I feel I have a better understanding now of the weapon.

With respect to the Israeli's use of/love of the gun.. I can't recall where I read about such, but it went into great detail (and supporting data) as to their love affair with it. Granted, it's likely far less applicable today. The time reference of the article seemed to focus on when they were flying with the MIrage III, although If I'm not mistaken some data for F-15 gun kills was also present. It may still be relevant, as stealth on stealth fights may wind up at the merge. If that's the case, and someone comes up with better IR countermeasures that complicates HOBS shots... the gun ammo will be immune to counter-measures.

So I was greatly heartened by your AV-8B anecdote. If I read that correctly, the F-35B will be flying into combat more often that not with its gun pod. Curious to see if that extends to the F-35C, as I'm sure it depends on the mission. Cruise missile defense? Unlikely. OCA/DCA? Possibly. Although they supposedly traded the gun for more gas in the B/C... I can see that in the case of the F-35B, but the C?

19,000 plus pounds of internal fuel would seem to be... plenty!

[blindpilot]

...

Crews has already commented that the USMC never flies the AV-8B on combat sorties without the gun system, and he did not see that changing with the Killer Bee. What the nasal radiators choose to do... I dunno...

Can't find a reference, and my old tired brain may have dreamed it after eating some spoiled mushrooms ...but I recall that ...

Without imputing what was meant by the quote, the guns on the Harrier are a bit more complicated in an aerodynamic sense. They often put them on when a high landing weight (bring back etc.) was expected because the vertical lift enhancement exceeded the gun system weight. Basically the two ridges on the fuselage side (gun and ammo pods) trapped a column of spill air near the deck/ground. That had as much of a reason that they carried the guns as needing bullets for the mission.

I don't expect that will apply to the "Bee".

FWIW MHO,
BP

[steve2267]

... the guns on the Harrier are a bit more complicated in an aerodynamic sense. They often put them on when a high landing weight (bring back etc.) was expected because the vertical lift enhancement exceeded the gun system weight. Basically the two ridges on the fuselage side (gun and ammo pods) trapped a column of spill air near the deck/ground. That had as much of a reason that they carried the guns as needing bullets for the mission.

I don't expect that will apply to the "Bee".

Blind, that is an excellent point.

As I recall, the Killer Bee receives a similar "lift boost" by opening the weps bay doors during VL. Leaving off the gun will net them some 900lbs of bringback or so...

Time will tell, then, to what extent the beloved Jarheads love their gunz.

[quicksilver]

Landing weight is an important consideration for anything that flies. Weight sensitivity is more acute for jets that land vertically because lift is provided almost exclusively by the propulsion system. The AE guys occasionally find useful (partial) mitigations — the so-called lift improvement devices (LIDS) on Harrier would be one example.

While descending In a vertical landing, STOVL propulsion systems actually create ‘lift’ (low pressure gradients) under the fuselage and wing of the jet as it descends into ground effect. This effect is referred to as ‘suck down.’ Consequently, it actually takes more thrust/lift to land than it does to hover. What the gun pods and/or strakes and LIDS fence do on Harrier is to capture/trap the jet efflux under the jet in a fashion that recovers some of the lift loss created by suck down effect. Additionally, the flaps (with the switch in the STOVL position) create positive recirculation of the efflux and are programmed to move with nozzle position. As suggested above, LIDS recovers about 1200# of lift during the last ~10-15’ of a VL. However, when the wind over the deck exceeds ~15 knots, this lift recovery is lost.

Gun plus ammo on Harrier II is ~1200#. Unlike the GR3/AV-8A, when the gun is not on the jet it has deep hanging fuselage strakes that perform the same LIDS functions — with a fraction of the weight penalty. Those gun pods can be a dramatic hit percentage-wise to one’s bring back and are carefully considered for mission necessity before configuration of the jet.

IIRC, F-35B weapons bay doors provide a much smaller lift recovery benefit but do function with or without the CL gun pod.

[blindpilot]

.... Unlike the GR3/AV-8A, when the gun is not on the jet it has deep hanging fuselage strakes that perform the same LIDS functions — with a fraction of the weight penalty. ....

Thanks for the info. I did not notice this on the move from A/SeaHarrier to II's. Probably because they mostly flew with guns? So they (USMC) must indeed like their guns.

BP

[Gums]

Salute!

Great points about the pods, and I only remembered the poor showing of the first ones we had back 40 years ago. Still not a fan of them due to many mechanical alignment thingies that can go south.
+++++++++++++++++++++++++++++++
P.S.

@Mixel PLZ stop posting an entire previous post!!!! Most of us have read the reference, and you only need to snip a line or phrase to make a point. Some of us do not have a) unlimited bytes for download and pay by the byte ( me in Colorado cabin on a satellite), b) actually read the previous posts leading up to the re-transmit of two pages of stuff with graphics and all.

Gums sends...

[quicksilver]

.... Unlike the GR3/AV-8A, when the gun is not on the jet it has deep hanging fuselage strakes that perform the same LIDS functions — with a fraction of the weight penalty. ....

Thanks for the info. I did not notice this on the move from A/SeaHarrier to II's. Probably because they mostly flew with guns? So they (USMC) must indeed like their guns.

BP

"It depends...". VL performance balanced against mission requirements. Put a couple tanks, some missiles, an ALQ and a T-pod on the jet and you may have a really heavy jet relative to VL performance (which depends on the specific engine/BuNo combination and the OAT). If you're in the Arabian Sea and its 110F, the gun may be a 'nice to have' because you wont have much VL performance and the gun is not jettison-able. So, the most frequent trade-off is fuel because PGMs are really expensive -- even the cheap ones. Folks flying conventional stuff almost pass out when they hear the amount of fuel that Harriers recover with on occasion (sometimes as a matter of routine, and without declaring an emergency). The good news is the first pass boarding probability is about .99999.

[steve2267]

QS, your statements above regarding loss of VL when the Wind Over the Deck (WOD) is 10-15+ knots... does that mean that the boat does not (or cannot?) conduct launch and recovery operations simultaneously or interleaved? E.g. launch one, recover one, launch one, recover... Because it would seem the launching aircraft would want as much WOD as possible.

Can VL'ing in a crosswind alleviate that loss of VL? Although VL'ing on the boat with the aircraft nose aligned 90° to the boat axis would seem to be a non-starter.

[quicksilver]

QS, your statements above regarding loss of VL when the Wind Over the Deck (WOD) is 10-15+ knots... does that mean that the boat does not (or cannot?) conduct launch and recovery operations simultaneously or interleaved? E.g. launch one, recover one, launch one, recover... Because it would seem the launching aircraft would want as much WOD as possible.

Can VL'ing in a crosswind alleviate that loss of VL? Although VL'ing on the boat with the aircraft nose aligned 90° to the boat axis would seem to be a non-starter.

Interleaved ops (as you describe it) are governed by circumstance and necessity. Loss of LIDS cushion is not a go/no-go factor. It just becomes something for the pilot to file away in his or her brain housing group when they're about to set state and make an approach. At higher WODs and lesser VL performance margins, one can typically expect to add lotsa power the last 10-15 feet of the VL to maintain a rate of descent that wont break the jet; "throttle in the corner" the last 10 feet is not rare when the jet is on or near its VL numbers and there's lotsa WOD going on. Also, an LSO will sometimes try to avoid recovering a jet to a spot with a jet idling immediately front of the landing spot for the same reason. If one has lotsa margin (i.e. VL performance is well in excess of the recovery weight of the jet) 'suck down' isnt much of an issue.

If the velocity is high enough, crosswinds do not alleviate the loss of LIDS effect.

[blindpilot]

....
Thanks for the info. I did not notice this on the move from A/SeaHarrier to II's. Probably because they mostly flew with guns? So they (USMC) must indeed like their guns.

"It depends...". VL performance balanced against mission requirements.

Thanks. It does make one wonder how Bee ops will go without any LID cushion offset from the gun pod. I suspect the F-135 set up has considerable power available, and the Brit SRVL procedures may take us to a new framework, such that it's "not an issue." (or at least not a major issue) ??
BP

PS. Hoping my JTAC grandson gets an LHD assignment next deployment, and I can debrief him some on his subsequent leave.

[quicksilver]

Brit SRVL adds 60kts of wing lift for a 25-40kt (relative speed) rolling landing; probably not a practical alternative for routine LHD use due to width of landing area and roll stability of the ship.

[spazsinbad]

'BP' in a previous post above 'QS' said this about the F-35B in last sentence:

"...IIRC, F-35B weapons bay doors provide a much smaller lift recovery benefit but do function with or without the CL gun pod."

In previous discussions (mostly in the SRVL thread) it seems the agreement is that SRVLs will not be done upon an LHA for reasons 'QS' hints at. Yes some USMC pilots will need to know how to do them IF the SRVL becomes a thing aboard CVFs because they may have to carry them out on a CVF with QE the most likely candidate when they embark in a few years.

One example of 'no SRVLs for LHAs' in other thread: viewtopic.php?f=22&t=20304&p=403896&hilit=roll#p403896

'QS' said: "...Ramps [ski jumps mentioned earlier by 'stevie'] do not obviate the principle challenge (as I mentioned above) which is the width of the available landing area. When combined with limits on deck motion (principally roll), the operating envelope would be very small."

[quicksilver]

Re: the IAF and gun discussion...

“Granted, it's likely far less applicable today.”

It depends. In the case if the IAF, they are defending their homeland — literally, their cities and towns and homes and families, and so on. That raises the level of allowable risk and changes the engagement criteria to something like, ‘remain on station, engage with all weapons until they are expended (short of ramming)...’

So, if you are an IAF fighter guy you had better be good at employment of everything you have on the jet — including the gun. They are, they have been, and I’m sure they will continue to be so in the future. It is always a matter of national survival.

[Corsair1963]

Do we know if the F-35 suffered any losses at Red Flag 19-1???