F-106 Delta Darts in the Vietnam War

[Dilandu]

How might Sidewinder armed F-106 "Six Shooters" (F-106s equipped with bubble canopies and Vulcan cannons) have performed during the Vietnam War? The F-106 had maneuverability on par with the F-4 Phantom II, being better in some situations and worse in others. It also carried an IRST system, which I'm not sure the F-4 carried. For purposes of this thread, we'll assume the "Six Shooters" are upgraded on a similar timetable as the USAF F-4s, gaining Sidewinders and Vulcans around the same time.

Okay, I checked the sources. The F-106 could NOT use Sidewinder, even if refitted to carry them in weapon bays.

The reason is: the Falcon missiles, that F-106 was designed to use, were pre-programmed on target while still inside the plane. The MA-1 fire control system aligned their seekers with the plane's radar, so missile lockèd on and tracked the target while still inside the closed weapon bay. The weapon bay doors opened for just 2 seconds to lower the missile launcher rail into air stream & launch it.

The Sidewinder could not be used like that. It have no pre-programming ability. It must lock on target with its own seeker - which took some time. And, well, F-106 simply not designed to fly for a long time with opened weapon bay, waiting while Sidewinder seeker gain the target. The aerodynamic problens would became intolerable.

So no, F-106 could not be refitted tò use Sidewinder. AIM-4H would be much better alternative.

 

[TsrJoe]

Convair F-106 Delta Dart Southeast Asia Camouflage Color Profile and Paint Guide

Here is our Convair F-106 Delta Dart Southeast Asia Camouflage Color Profile and Paint Guide.

www.cybermodeler.com

 

[Archibald]

How might Sidewinder armed F-106 "Six Shooters" (F-106s equipped with bubble canopies and Vulcan cannons) have performed during the Vietnam War? The F-106 had maneuverability on par with the F-4 Phantom II, being better in some situations and worse in others. It also carried an IRST system, which I'm not sure the F-4 carried. For purposes of this thread, we'll assume the "Six Shooters" are upgraded on a similar timetable as the USAF F-4s, gaining Sidewinders and Vulcans around the same time.

Okay, I checked the sources. The F-106 could NOT use Sidewinder, even if refitted to carry them in weapon bays.

The reason is: the Falcon missiles, that F-106 was designed to use, were pre-programmed on target while still inside the plane. The MA-1 fire control system aligned their seekers with the plane's radar, so missile lockèd on and tracked the target while still inside the closed weapon bay. The weapon bay doors opened for just 2 seconds to lower the missile launcher rail into air stream & launch it.

The Sidewinder could not be used like that. It have no pre-programming ability. It must lock on target with its own seeker - which took some time. And, well, F-106 simply not designed to fly for a long time with opened weapon bay, waiting while Sidewinder seeker gain the target. The aerodynamic problens would became intolerable.

So no, F-106 could not be refitted tò use Sidewinder. AIM-4H would be much better alternative.

The F-106 had external wing pylons for a pair of streamlined drop tanks. Maybe Sidewinders could be hanged there to do the job (bolded).

 

[Dilandu]

The F-106 had external wing pylons for a pair of streamlined drop tanks. Maybe Sidewinders could be hanged there to do the job (bolded).

But whats the point? It would not give F-106 much advantages. Its main advantage is exactly the sophisticated fire control system, that could lock Falcon missile on target long before launch. Replacing it with Sidewinder would force pilot to aim manually, hold sight on target for missile lock-on, instead of just pushing the switch and giving the controls to computer.

 

[Archibald]

Did not said the contrary. Red some air combat stories from the 60's, where they did exactly that: they left the AIM-9(B) seeker doing the lock on the target, all by itself. No help for any radar or pilot or aircraft.
Bottom line: wasn't very efficient, or did not worked at all. Must have been the Israelis, or the Pakistanis against the Indians.

 

[Dilandu]

Did not said the contrary. Red some air combat stories from the 60's, where they did exactly that: they left the AIM-9(B) seeker doing the lock on the target, all by itself. No help for any radar or pilot or aircraft.

That's the whole point. The Sidewinder needed to aquire the target by itself. So the pilot was forced to aim it - by aiming the whole plane - on the enemy, and hold the enemy in crosshair for a few seconds, till Sidewinder would lock on it.

With the Falcon & MA-1 fire control system, it was much easier. The missile started to lock on target as soon as plane's radar locked on target. Radar have MUCH more range than missile seeker, and did not require any pilot's efforts to track the target - so the missile was prepared to launch long before the launch itself. As soon as fighter came into missile range, Falcon launched automatically, being already locked on target.

 

[aim9xray]

Not exactly. By the late 60s SEAM (Sidewinder Extended Acquisition Mode) was developed and being implemented. Part of SEAM was a modified Sidewinder interface that allowed the aircraft AMCS to provide signals to position the Sidewinder seeker to the projected target position (even it optically blanked by aircraft structure) so that target acquisition would be immediate after the missile came off the rail. (A "hey! look over there" function if you will.)

SEAM was installed in Navy F-4Js along with VTAS (early helmet-mounted sight) before the end of the Vietnam war.

 

[Dilandu]

Not exactly. By the late 60s SEAM (Sidewinder Extended Acquisition Mode) was developed and being implemented. Part of SEAM was a modified Sidewinder interface that allowed the aircraft AMCS to provide signals to position the Sidewinder seeker to the projected target position (even it optically blanked by aircraft structure) so that target acquisition would be immediate after the missile came off the rail. (A "hey! look over there" function if you will.)

Hm! Didn't know that, thank you!

 

[thefrecklepuny]

I had an old book on the F-15 and its development. It mentioned that F-106's along with F-4's were used as adversary aircraft, officially mimicking MiG-23's. They did pretty well, apparently often giving the Eagle's a harder time than expected.

 

[uk 75]

The F102 Delta Dagger served widely with the USAF overseas both in Asia and Europe.

Convair F-102 Delta Dagger - Wikipedia

en.m.wikipedia.org

Its replacement was not the F106 with these units but the F4 which was multi-role.

The F106 was not upgraded as once planned but served with US Air Defence units until F15 and F16 aircraft were available in sufficient numbers.

 

[Pioneer]

I always liked the idea of F-106's being adapted to strike/interdiction platforms with the advent of the Paveway PGB.
By stripping out it's weapons bay of all the affiliated Falcon and Genie supporting equipment (and perhaps even their trapeze pylons to make further room?), giving room for two (or hopefully three) Paveway PGB's
A AN/AVQ-10 Pave Knife targeting pod replacing one of the two drop tanks usually carried by the F-106, so as to paint targets.

As such, the clean lines of the F-106's inherent internal weapons carriage and hence high and clean performance allows the F-106 to enter hostile aerospace much faster than anything else the USAF/USN has to minimise their exposure to both enemy ground-based air defence systems and air interception alike - as such the Thanh Hóa Bridge is only but the first strategic target eliminated in North Viet Nam, with minimal lose of U.S. aircraft and crews alike....

P.S. Can anyone confirm whether the Paveway PGB can actually be dropped at supersonic speed?

Regards
Pioneer

 

[MadRat]

Probably had room for for one centerline 2,000 pound paveway, but only by doing major modifications. I expect performance to nosedive with such a heavy payload. Probably have to add canards like on the Mirage 5 to stabilize the nose authority.

Sidewinder could have been carried under additional wing pylons, but that again is a major modification.

 

[Rule of cool]

Here's a crazy thought. The weapons bay of the F106 is pretty big, fill it with fuel and a gun. Then replace the doors with semi recessed hardpoints for sparrows and put a single sidewinder on the wing pylons. Bingo!

 

[BLACK_MAMBA]

Here's a crazy thought. The weapons bay of the F106 is pretty big, fill it with fuel and a gun. Then replace the doors with semi recessed hardpoints for sparrows and put a single sidewinder on the wing pylons. Bingo!

Wonder how difficult it would be to develop dual Sidewinder and fuel tank pylons for the Six? Naturally accepting the drag penalty for the extra weapons load. There is a Naval F-106 proposal on the forum with 4 x Sparrow in the main bay. No space for a gun though.

The next question though is considering the Six was entirely built around the Aim-4 and its weapon system, would it not be easier to finish the Aim-4H and go to war with that? Less airframe design changes risk and you get the gun too.

 

[Rule of cool]

The wing tanks look pretty close to the main landing gear, so clearance might be a problem if too much is tried.

All I know about the Aim4 family is that in combat it was garbage. Would the aim4h development not be garbage, and would it be in service in time for Rolling Thunder?

 

[pathology_doc]

The wing tanks look pretty close to the main landing gear, so clearance might be a problem if too much is tried.

All I know about the Aim4 family is that in combat it was garbage. Would the aim4h development not be garbage, and would it be in service in time for Rolling Thunder?

AIM-4H would be relieved of one of the problems that made it garbage, i.e. the need for a direct hit, and it probably would have had other performance/reliability improvements built in. @SOC 's article at ausairpower.com makes it clear that some of the misses were very narrow indeed, and might have been converted to kills if the weapon had had a proximity fuze.

AIM-4D's percentage kill rate isn't that different from Sparrow's; the difference is that all of AIM-4D's kills were direct hits by definition. AIM-9B has a worse seeker (uncooled, unsophisticated), but it doesn't suffer from the issue AIM-4D did of running out of coolant if a target couldn't be engaged in time. Later Sidewinders DID have a cooled seeker, but I still can't understand why AIM-4D has a problem here and cooled-seeker Sidewinders do not.

 

[Michel Van]

Video about F-106 Six Shooter

View: https://www.youtube.com/watch?v=9sD7cOpBgJQ


Additional stuff

View: https://www.youtube.com/watch?v=7yUlwzHOpdU


1965 Interceptor Competition: F-106 vs other fighters

View: https://www.youtube.com/watch?v=OstMrYEl-tw

 

[TsrJoe]

TO. 1-1-4 drawing for F-106

 

[MadRat]

Cooled-seeker AIM-9's utilized high seeker rates to scan for a target. Falcon was provided that information. Just makes me think that F-106 was well-suited to command link technology if computer technology had been better in its day. F-106 could have launched from longer distances and corrected the missile as the target vectors changed. AIM-54 was probably a natural fit, considering it evolved from the Falcon family. F-106 with 1, 2, or 3 AIM-54 loadouts wasn't as far fetched as internal sidewinders.

 

[pathology_doc]

F-106 with 1, 2, or 3 AIM-54 loadouts

AIM-54 is a MUCH bigger missile, and heavier too (in the neighbourhood of 1000lb, as opposed to 150-ish for most Falcons). I'm not sure the Six would be able to carry it internally, and external carry is going to seriously affect the Six's performance.

The other part of Phoenix is that the uplink to change the midcourse targeting requires a completely different weapon system from the one that the Six is fitted with to start with. Do you even have the internal volume to fit the entire AWG-9 suite?

"Fit the F-106 with the AIM-54 missile" is not as easy as it sounds, and the changes needed to the Six to enable what you've suggested might find you concluding that a clean-sheet-of-paper design is better.

 

[Scott Kenny]

AIM-4H would be relieved of one of the problems that made it garbage, i.e. the need for a direct hit, and it probably would have had other performance/reliability improvements built in. @SOC 's article at ausairpower.com makes it clear that some of the misses were very narrow indeed, and might have been converted to kills if the weapon had had a proximity fuze.

AIM-4D's percentage kill rate isn't that different from Sparrow's; the difference is that all of AIM-4D's kills were direct hits by definition. AIM-9B has a worse seeker (uncooled, unsophisticated), but it doesn't suffer from the issue AIM-4D did of running out of coolant if a target couldn't be engaged in time. Later Sidewinders DID have a cooled seeker, but I still can't understand why AIM-4D has a problem here and cooled-seeker Sidewinders do not.

2 related problems:
1) CONOPS in general, AIM-4 was designed around having the plane guided to the intercept by the SAGE system and told where the target would be before the bay even opened. So it wasn't ever intended to be a dogfighting missile, but a small bomber-killer.
2) that it only had 2 minutes(!) of coolant onboard the launcher when the cooled AIM-9s had 30 minutes of coolant. The minimal amount of coolant onboard goes back to the CONOPS, but it certainly could have been increased if someone had thought about it during the design phase of the F-4D.

But seriously, who would have thought that the US would get into a shooting war with Positive Visual ID requirements?!?

 

[MadRat]

AIM-54 is a MUCH bigger missile, and heavier too (in the neighbourhood of 1000lb, as opposed to 150-ish for most Falcons). I'm not sure the Six would be able to carry it internally, and external carry is going to seriously affect the Six's performance.

I didn't suggest it was smaller.

The other part of Phoenix is that the uplink to change the midcourse targeting requires a completely different weapon system from the one that the Six is fitted with to start with. Do you even have the internal volume to fit the entire AWG-9 suite?

"Fit the F-106 with the AIM-54 missile" is not as easy as it sounds, and the changes needed to the Six to enable what you've suggested might find you concluding that a clean-sheet-of-paper design is better.

I'm confident Hughes could figure out their equipment. AIM-54 was not limited to or specifically tied to AWG-9, it simply was the only system used with it. F-106C was to internally carry one (dimensionally bigger) AIM-47 and two AIM-26. And F-106 did have provsions for mid-wing mounts. They just were not used in standard operations. They were rated shy of 2,000 pounds, plenty of capacity for weilding the AIM-54.

 

[pathology_doc]

F-106C was to internally carry one (dimensionally bigger) AIM-47 and two AIM-26.

F-106Cs would all have been new-build aircraft, designed from the start around that missile fit. You might adapt that to Phoenix, but retrofitting the -A or the -B is quite another matter.

 

[MadRat]

Reworking the airframe for the different J75 variant is minor. The nose was getting a 40" radome that came out of the F-108 program. The bigger nose was more significant. The command wanted bigger and better airframes, leading to discussion of alternatives that included F-106-30 and F-106E. The F-106C was a minor change from the F-106A.

 

[Christopher Wang]

How'd you carry Sidewinders on them? Isn't the F-106 bay rather specifically designed around the Falcons?

As shown in this post, there were proposals to turn the F-106 Delta Dart into a tactical fighter-bomber equipped with four external underwing hardpoints and a modified weapons bay. The underwing stations and weapons bay were planned to carry a combination of fuel tanks, general-purpose conventional bombs, AIM-9 Sidewinders, AGM-12 Bullpups, gun packages, and special weapons (Barbier, 2017).


SOURCE: Barbier, D. (2017). World's Fastest Single-Engine Jet Aircraft: The Story of Convair's F-106 Delta Dart Interceptor. Specialty Press.

 

[MadRat]

F-106 wasn't a dogfighter so a better Falcon probably benefits the platform more than Sidewinder. F-106 high closure speed was its prime asset. The cruise speed of F-106 would have degraded external Sidewinders, so internal is pretty much the only option short of taking the F-106 down to a much more vulnerable cruise profile. Mid-wing Sparrow on the other hand doesn't share those limitations.