May I add, size and weight - aka spotting factor of the F-8 Crusader vs. Sea Vixen.

Also, given the time frame, perhaps consider the incorporation of the off-the-shelf Magnavox AN/APQ-94 radar and Aim-9C of the Vought F-8 Crusader into P.1127 design.
I acknowledge that the the AN/APQ-94 radar and Aim-9C might not have been an ideal radar and missile. But let's be realistic, what radar and missile was in the 1960's.
At the end of the day, this would be a far cheaper, less risk solution of giving the P.1127/Royal Navy an all-weather interceptor capability, long before the tailored-made Sea Harrier and its Ferranti Blue Fox radar was brought about.


Regards
Pioneer
The biggest problem with this idea is that it kicks the UK's in-house radar design and development teams in the wedding tackle.

Like I said, the biggest issue the UK R&D folks seem to have is focus and saying "it works well enough here, we can move the next things we want to do to the next generation and get this version deployed now."

The second largest problem is that APQ-94 and AIM-9Cs must be bought in USD, and dollars are a limited item in the 1950s/60s UK economy.
If it helps many of the Javelins and Meteor night fighters had US supplied radars and much of the avionics for the Spey-Phantom was British built, including the AWG-10 radar that Ferranti built under licence.
 
The biggest problem with this idea is that it kicks the UK's in-house radar design and development teams in the wedding tackle.

Like I said, the biggest issue the UK R&D folks seem to have is focus and saying "it works well enough here, we can move the next things we want to do to the next generation and get this version deployed now."

The second largest problem is that APQ-94 and AIM-9Cs must be bought in USD, and dollars are a limited item in the 1950s/60s UK economy.
Scott Kenny, I fully appreciate your analogy, in terms of both indigenous industry and economic constraints.
The fact was, as much as British industry and scientists irrufutably had the brains and know how, the fact remains that time and time again, indigenous industry and know how often failed to deliver in a timely manner.
This is perhaps why the APQ-94 and AIM-9Cs could get the navalised P.1127 into service in it's first iteration ['it works well enough here, and get this version deployed now.']. With British industry 'moving to develop the next things we want to do to the next generation'.

Regards
Pioneer
 
Scott Kenny, I fully appreciate your analogy, in terms of both indigenous industry and economic constraints.
The fact was, as much as British industry and scientists irrufutably had the brains and know how, the fact remains that time and time again, indigenous industry and know how often failed to deliver in a timely manner.
This is perhaps why the APQ-94 and AIM-9Cs could get the navalised P.1127 into service in it's first iteration ['it works well enough here, and get this version deployed now.']. With British industry 'moving to develop the next things we want to do to the next generation'.

Regards
Pioneer
That doesn't really fix the issues with British Industry, unfortunately.

Yes, it gets the minimum capability into service. And you might be able to make an enlarged rocket for the AIM-9Cs for more range (think "radar Sparrowinder").

But it doesn't get the radar boffins thinking "is what we have right now good enough for service"...
 
The big problem with an early pivot to the P1127, especially fitting it with a radar, is a lack of engine power from the Pegasus. The Kestrel of 1964 only had 15,000lbs, and the GR1 of 1969 only 19,000lbs, not much to tote around a radar in the nose and counterweight in the rear fuselage.
 
Now that's an appealing idea... putting SARH into the Harrier through Crusader rather than Phantom.
 
Didn't the F-105 get something like two dozen documented kills with the internal gun? And that was an aircraft whose primary mission was attack bomber.

24.5 with guns and 3 with Aim9s, all Mig 17s. The F105 never shot down a Mig 21, but many F105s were shot down by Mig 21s.

AAMs were an improvement over guns in the 60s, but hindsight showed that guns were an effective backup weapons as those early sidewinders only worked about 10% of the time.
 
Yes, it gets the minimum capability into service. And you might be able to make an enlarged rocket for the AIM-9Cs for more range (think "radar Sparrowinder").

But it doesn't get the radar boffins thinking "is what we have right now good enough for service"...
1. Or stick the AIM-9C electronics into the nose of a Red Top, a missile the Royal Navy was experienced with and understood well.

2. No, it doesn't, but IIRC there were multiple attempts to get Radar Red Top off the ground that weren't persisted with to a solution because the powers that be are always loath to pay for it, and in the end what happens? Britain dodges that responsibility in the short term and buys Sparrow along with the Phantom.

Meanwhile, Taildog seems to work well but never goes into production (which is a shame since the Harrier could probably have carried twice as many Taildogs as Sidewinders in the Falklands), and the British AAM comeback consists of making Sparrow great again (to the point where the Swedes buy it for the Viggen).

I suspect that if the Royal Navy had gone down the through-deck-cruiser-with-Harrier pathway from an earlier stage, Taildog WOULD have gone into service.
 
1. Or stick the AIM-9C electronics into the nose of a Red Top, a missile the Royal Navy was experienced with and understood well.

2. No, it doesn't, but IIRC there were multiple attempts to get Radar Red Top off the ground that weren't persisted with to a solution because the powers that be are always loath to pay for it, and in the end what happens? Britain dodges that responsibility in the short term and buys Sparrow along with the Phantom.
Sure, that'd be another option to consider. Range of Red Top really just sucks, though. 12km. Sparrow-sized warhead with Sidewinder range. Though that heavy warhead may be preferable versus jet heavy bombers, the range makes me really uncomfortable.



Meanwhile, Taildog seems to work well but never goes into production (which is a shame since the Harrier could probably have carried twice as many Taildogs as Sidewinders in the Falklands), and the British AAM comeback consists of making Sparrow great again (to the point where the Swedes buy it for the Viggen).

I suspect that if the Royal Navy had gone down the through-deck-cruiser-with-Harrier pathway from an earlier stage, Taildog WOULD have gone into service.
Absolutely agree here, Taildog is one of my absolute favorite "what-if"/"if-only" missiles. Been debating equal weight of Taildog versus Aden pods on Harrier, for example. (2x ADEN with 200rds being ~400kg, and I'm guesstimating the twin-mount AST1218 SRAAM as ~150-200kg. So in that case two twin-SRAAM boxes would be right about the same weight or a bit lighter than the classic pair of ADEN guns under a Harrier.)
 
So in that case two twin-SRAAM boxes would be right about the same weight or a bit lighter than the classic pair of ADEN guns under a Harrier.
Or two for one on the outer hardpoints where the Sidewinders go, and keep the guns.

Or the batteries?
I'd need to know a whole lot more about Red Top than I actually do to answer that question. Ultimately they were all designed to detonate after about 11 or 13 seconds, when it was estimated that they'd run out of kinetic energy and were more of a hazard to friend than foe. Putting in a longer-duration power supply and/or a better motor would be part of the upgrade, though I can't see a Harrier carrying more than two (Red Top weighs 330lb, Sidewinder in its heaviest iterations close to 200, Sparrow somewhere between 450lb in earlier versions up to just over 500 for the final).

Oddly enough, Red Top weighs about the same as AMRAAM, although the fins are bigger and there could be clearance issues carrying more than two even if weight and drag were no problem.
 
But is that a function of the missile, or a function of the seeker?

Apparently the seeker could detect an F4K in afterburner head-on at 21km.
Sure, that'd be another option to consider. Range of Red Top really just sucks, though. 12km. Sparrow-sized warhead with Sidewinder range.

Under what circumstances is the Red Top range 12km? In the same circumstances what is the Range of the Matra R530, AIM 7E and AIM 9D?

If a Red Top could be fired head-on at a Mach 1.5 target flying at 47,000' at 21km and tail chase 4.1km what is the range?
 
Given the sort of target Red Top is intended to kill head-on, a Harrier-sized fighter in the 1960s arguably couldn't carry a radar big enough to illuminate for Sparrow beyond that distance anyway. The Lightning has a similar problem due to the size of its radome (assuming that enabling SARH illumination is a done deal).

Initial thoughts about putting Sea Dart on the Sea Vixen crashed and burned for similar reasons, IIRC: the missile had huge reserves of kinematic performance it couldn't use because the interferometer guidance head's sensitivity was matched to a big-ass SARH illuminator on a warship and an aircraft (except maybe a Vulcan) just couldn't manage that.
 
Because it annoys me, comes up so regularly and there's no real answer to 'range' I've thrown together a bit of a table of the mid 60s Western AAM rockets. The dimensions of the missiles are pretty well known so the thrust, burn times and top speeds will give an idea of the comparative performance of various missiles. This is a quick lash-up, if people have better figures for these parameters I'd love to see them, as I think this is a better indication of what missile can do what and how.

Red Top
  • Linnet, diameter 7.25in (18.4cm) x length 39in (99cm)
  • Thrust 8,000lbf - 5,000lbf (low-high altitude)
  • Burn time - 3 seconds
  • Mach 3.2
Aim9D
  • Hercules/Bermite MK 36 Solid-fuel rocket
  • Thrust: 2880lbs (1306kg)
  • Burn time - 5 seconds
  • Mach 2.5
Aim9E
  • Thiokol MK 17 solid-fuel rocket
  • Thrust: 4200lbs (1905kg)
  • Burn time - 2.2 seconds
  • Mach 2.5
AIM-7E
  • Rocketdyne MK 38/MK 52 solid rocket
  • Thrust: 7600lbs (3447kg)
  • Burn time - 2.9 seconds
  • Mach 4
R.530
  • Hotchkiss-Brandt/SNPE Antoinette rocket
  • 18,740lb (boost) Wow, who'da thunk it!
  • Burn time - 2.7 s + 6.5 s cruise
  • Mach 2.7
 
The dimensions of the missiles are pretty well known so the thrust, burn times and top speeds will give an idea of the comparative performance of various missiles.
What we don't have is:
a) Drag coefficient (which, depending on the source you read, can be dependent on either the Mach number OR both the Mach number and the Reynolds Number).
b) Altitude at which the range is calculated (drag = drag coefficient x dynamic pressure x Cd reference area, and dynamic pressure is linearly dependent on density, which is an exponential function of altitude).
c) Specific impulse of the rocket fuel, and quantity burned.
d) Thrust-time curve.

Range under power = velocity x Isp x sustainer charge weight/drag (for a boost-sustain missile).
Range under coast is much more complicated, because you have to iteratively recalculate Cd for the current mach number as you slow down.
The designers of Red Top chose a hemispherical nose for whatever reason despite the fact that it has a higher drag coefficient than any cone or ogive (Firestreak was better in this regard), so Red Top (which IIRC is a boost-glide missile) is going to suffer badly once it's burned its fuel (and by the way, rocket thrust should be HIGHER at higher altitude).
AIM-7E follows the burn time stated with a sustain burn of several more seconds (per Tactical Missile Design, G Fleeman).
R.530 does sound like an error. Thrust = Isp x charge weight/burn time, and if you have a long enough motor with enough burn surface area and a fast enough propellant in terms of linear burn rate, you can turn out some really fantastic numbers. That being said, the printed examples I've seen in literature which give that much thrust are large tandem boosters for surface-air missiles which weigh more than the R.530 does at launch.

Even trying to reverse-engineer the drag coefficient from the burnout velocity can be difficult, because the equations that calculate burnout velocity do so as a CHANGE in velocity over that of the launch platform, and while the first approximation equation doesn't depend on the drag, the more refined one most definitely does. The correction factor is (1- [(average drag)/thrust]), with an iteration to get the hypothetical zero-drag burnout velocity for the high value and the speed of the launch aircraft to get the low value.

I think it's time to start a topic to discuss what a missile's performance figures (as published in Mr Average Bill Gunston book of the 1980s) actually mean. @overscan (PaulMM) , where do you think is the best place to put it?
 
I agree, but a couple of sources stated it.

The Aim9D burn time looks too long. War thunder Wiki says 3.5 seconds, which looks more accurate, but its War Thunder so I'm dubious.
For the sparrow, I've seen 20-30k lbf*s, which would be the impulse, I think... So the 18700 for the R530 may be just that, divided by 2.7s would give 7000 pounds (lbf ? High school physics is a long time past) thrust?
 
For the sparrow, I've seen 20-30k lbf*s, which would be the impulse, I think... So the 18700 for the R530 may be just that, divided by 2.7s would give 7000 pounds (lbf ? High school physics is a long time past) thrust?
Total impulse is the area under the curve for thrust vs time, i.e. for 2000lb thrust over 20 seconds it would be 40,000lb.sec.

Fleeman (Tactical missile design 1st Edition) has a set of theoretical calculations for "rocket baseline missile" based on declassified AIM-7 data: 5750lb for 3.26 seconds in boost, 1018 lb for 10.86s duration at 20,000 feet in the ICAO standard atmosphere (page 196). Total: 29,800 lbf.sec, so your 20-30K is as close to the upper bound as makes no difference.
 
I made this post to continue the in-depth missile performance discussion: https://www.secretprojects.co.uk/th...hat-does-that-range-figure-really-mean.51334/

Specific theorizing about which missiles a putative early AH Sea Harrier should carry might best be limited to comparing nominal ranges for various weapons from a given authority (e.g. Christopher Chant's Modern Air Weapons) as a relative indicator.

In terms of the British missiles, things are difficult because AFAIK none of them were ever fired in anger and shots vs. drones (even with challenging geometry) simply don't have the same urgency.
 
I made this post to continue the in-depth missile performance discussion: https://www.secretprojects.co.uk/th...hat-does-that-range-figure-really-mean.51334/

Specific theorizing about which missiles a putative early AH Sea Harrier should carry might best be limited to comparing nominal ranges for various weapons from a given authority (e.g. Christopher Chant's Modern Air Weapons) as a relative indicator.

In terms of the British missiles, things are difficult because AFAIK none of them were ever fired in anger and shots vs. drones (even with challenging geometry) simply don't have the same urgency.

I put my figures from above in that thread.
 
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