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stephenmcparlin

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  1. DH Venom

    stephenmcparlin reviewed paulopanz's file in Other

  2. I'm intrigued... I'm experimenting with modifying some of the DATA.ini to upgrade/refine some of the models I've seen, for research purposes, and potential release back into the collective. I've been reverse engineering some of the object descriptions in the DATA.ini files to enhance realism, but I've not looked at modding geometry yet. I have significant background in *real* CAD (CATIA V5 and similar goodies), but not the simplified polygonal model builders used in simulation. A project... I'm trying to work out how to get the full spectrum of weapons/radar fits on some older warships working, with a little success. I suspect this is going to involve adding logical hierarchies to models to ensure that these are correctly located and have appropriate system logic trees to sustain them. Stephen McParlin ACGI, BEng., CEng., AFAIAA, FRAeS p.s. I'm an old, and very clued up engineer, who knows things...

  3. SF2 SAMs Pack

    stephenmcparlin commented on eburger68's file in Ground Object Mods

    I've managed to get a working Rapier SAM battery. But... it requires mods to the EW Radar data.ini file to set the network to the right values for the version of Rapier in use. Also, to enable the launcher to traverse, elevate and fire, requires that some of the commented-out parameters in the data.ini files for the launchers need to be restored. I've finally gotten to the point where Rapier systems can fire at and kill aircraft.
  4. Thanks... I have now been successfully (!?) shot down by a working Rapier site. The key lies in making modifications to the files in the SAM packs. The EW Radar item is set for a non-existent network, RapierSAM, which needs to be edited depending on which variety of Rapier you're using, as the 1E and 2A field standards have different network identifiers from the basic derivative. The files describing the launchers need to be modified too, as, critically, the lines decribing the azimuth and elevation of the launchers have been commented out, and need to be restored. With the restored settings, my advice when crossing targets defended by Rapier sites (EW Radar, Blindfire radar and Rapier Launcher) is to stay high enough or move fast enough to make it difficult for them to track or reach you. Rapier is a SACLOS-guided hit-to-kill weapon, and even with the radar systems taken out, it can still engage optically, if you're close enough. Rapier was exported widely, including to the US, who used it for protecting USAF bases in the UK from the mid 1980s until the end of the Cold War.
  5. I've been trying to work out how to plug together SAM sites for Blue. Some of these (Hawk, Patriot, Bloodhound, Nike) work pretty well, once you've identified the appropriate surveillance and tracking radars. There are some limitations. The usual configuration for a Bloodhound site involves eight missiles and a mobile Type 86 radar. It's not too dissimilar from the classic SA-2 site. But... the one real bugbear. I've not managed to find a working configuration for Rapier, either in the Mk. 1, 1E or 2 forms available in the SAM packages. It's puzzled me, as I've been able to fly ferret missions where the Blindfire radars acquire me, but no response from any of the launchers. I'd be keen to know what I'm missing.

  6. Jaguar GR3A For SF2

    stephenmcparlin replied to mikeymead's topic in Thirdwire: Strike Fighters 2 Series - File Announcements

    Modified LOADOUT.INI // Station 1 = Left Wing Station Outboard // Station 2 = Right Wing Station Outboard // Station 3 = Left Wing Station Inboard // Station 4 = Right Wing Station Inboard // Station 5 = Left Top Wing // Station 6 = Right Top Wing // Station 7 = Centerline Station [AirToAir] Loadout[01].WeaponType=AIM-9L Loadout[01].Quantity=1 Loadout[02].WeaponType=AIM-9L Loadout[02].Quantity=1 Loadout[03].WeaponType=TANK_NADR Loadout[03].Quantity=1 Loadout[04].WeaponType=TANK_NADR Loadout[04].Quantity=1 Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 Loadout[07].WeaponType=ALQ-101GREY Loadout[07].Quantity=1 [AirToAirLongRange] Loadout[01].WeaponType=AIM-9L Loadout[01].Quantity=1 Loadout[02].WeaponType=AIM-9L Loadout[02].Quantity=1 Loadout[03].WeaponType=TANK_NADR Loadout[03].Quantity=1 Loadout[04].WeaponType=TANK_NADR Loadout[04].Quantity=1 Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 Loadout[07].WeaponType=TANK_NADR Loadout[07].Quantity=1 [Attack] Loadout[01].WeaponType=ALQ-101GREY Loadout[01].Quantity=1 Loadout[02].WeaponType=Phimat-UK Loadout[02].Quantity=1 Loadout[03].WeaponType=RBL755 Loadout[03].Quantity=2 Loadout[03].RackType=2BR_uk_jag Loadout[04].WeaponType=RBL755 Loadout[04].Quantity=2 Loadout[04].RackType=2BR_uk_jag Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 Loadout[07].WeaponType=TANK_NADR Loadout[07].Quantity=1 Loadout[01].WeaponType=ALQ-101GREY Loadout[01].Quantity=1 Loadout[02].WeaponType=Phimat-UK Loadout[02].Quantity=1 Loadout[03].WeaponType=Mk22_1000_LD Loadout[03].Quantity=2 Loadout[03].RackType=2BR_uk_jag Loadout[04].WeaponType=Mk22_1000_LD Loadout[04].Quantity=2 Loadout[04].RackType=2BR_uk_jag Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 Loadout[07].WeaponType=TANK_NADR Loadout[07].Quantity=1 [sEAD] Loadout[01].WeaponType=ALQ-101GREY Loadout[01].Quantity=1 Loadout[02].WeaponType=Phimat-UK Loadout[02].Quantity=1 Loadout[03].WeaponType=RBL755_2 Loadout[03].Quantity=2 Loadout[03].RackType=2BR_uk_jag Loadout[04].WeaponType=RBL755_2 Loadout[04].Quantity=2 Loadout[04].RackType=2BR_uk_jag Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 Loadout[07].WeaponType=TANK_NADR Loadout[07].Quantity=1 [Anti-Ship] Loadout[01].WeaponType=ALQ-101GREY Loadout[01].Quantity=1 Loadout[02].WeaponType=Phimat-UK Loadout[02].Quantity=1 Loadout[03].WeaponType=Mk22_1000_LD Loadout[03].Quantity=2 Loadout[03].RackType=2BR_uk_jag Loadout[04].WeaponType=Mk22_1000_LD Loadout[04].Quantity=2 Loadout[04].RackType=2BR_uk_jag Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 Loadout[07].WeaponType=TANK_NADR Loadout[07].Quantity=1 [FAC] Loadout[01].WeaponType=Matra-155 Loadout[01].Quantity=1 Loadout[02].WeaponType=Matra-155 Loadout[02].Quantity=1 Loadout[03].WeaponType=TANK_NADR Loadout[03].Quantity=1 Loadout[04].WeaponType=TANK_NADR Loadout[04].Quantity=1 Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 [Recon] Loadout[01].WeaponType=ALQ-101GREY Loadout[01].Quantity=1 Loadout[02].WeaponType=ALQ-101GREY Loadout[02].Quantity=1 Loadout[03].WeaponType=TANK_NADR Loadout[03].Quantity=1 Loadout[04].WeaponType=TANK_NADR Loadout[04].Quantity=1 Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 Loadout[07].WeaponType=RECCE_POD Loadout[07].Quantity=1

  7. Jaguar GR3A For SF2

    stephenmcparlin commented on mikeymead's file in Jaguar

    I've had to modify the LOADOUT.INI file to get the SEAD option to work. Note that the original misses out one of the twin boom rails on the inboard pylon. I found an alternative that worked. The resulting version is a little more representative of the service aircraft. One other thought. During Operation Granby, in 1991/92, the CRV-7 rocket was purchased under a UOR, and that's a more suitable alternative to the Matra 155 68mm rocket pods So, here's the text of the modified file: // Station 1 = Left Wing Station Outboard // Station 2 = Right Wing Station Outboard // Station 3 = Left Wing Station Inboard // Station 4 = Right Wing Station Inboard // Station 5 = Left Top Wing // Station 6 = Right Top Wing // Station 7 = Centerline Station [AirToAir] Loadout[01].WeaponType=AIM-9L Loadout[01].Quantity=1 Loadout[02].WeaponType=AIM-9L Loadout[02].Quantity=1 Loadout[03].WeaponType=TANK_NADR Loadout[03].Quantity=1 Loadout[04].WeaponType=TANK_NADR Loadout[04].Quantity=1 Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 Loadout[07].WeaponType=ALQ-101GREY Loadout[07].Quantity=1 [AirToAirLongRange] Loadout[01].WeaponType=AIM-9L Loadout[01].Quantity=1 Loadout[02].WeaponType=AIM-9L Loadout[02].Quantity=1 Loadout[03].WeaponType=TANK_NADR Loadout[03].Quantity=1 Loadout[04].WeaponType=TANK_NADR Loadout[04].Quantity=1 Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 Loadout[07].WeaponType=TANK_NADR Loadout[07].Quantity=1 [Attack] Loadout[01].WeaponType=ALQ-101GREY Loadout[01].Quantity=1 Loadout[02].WeaponType=Phimat-UK Loadout[02].Quantity=1 Loadout[03].WeaponType=RBL755 Loadout[03].Quantity=2 Loadout[03].RackType=2BR_uk_jag Loadout[04].WeaponType=RBL755 Loadout[04].Quantity=2 Loadout[04].RackType=2BR_uk_jag Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 Loadout[07].WeaponType=TANK_NADR Loadout[07].Quantity=1 Loadout[01].WeaponType=ALQ-101GREY Loadout[01].Quantity=1 Loadout[02].WeaponType=Phimat-UK Loadout[02].Quantity=1 Loadout[03].WeaponType=Mk22_1000_LD Loadout[03].Quantity=2 Loadout[03].RackType=2BR_uk_jag Loadout[04].WeaponType=Mk22_1000_LD Loadout[04].Quantity=2 Loadout[04].RackType=2BR_uk_jag Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 Loadout[07].WeaponType=TANK_NADR Loadout[07].Quantity=1 [sEAD] Loadout[01].WeaponType=ALQ-101GREY Loadout[01].Quantity=1 Loadout[02].WeaponType=Phimat-UK Loadout[02].Quantity=1 Loadout[03].WeaponType=RBL755_2 Loadout[03].Quantity=2 Loadout[03].RackType=2BR_uk_jag Loadout[04].WeaponType=RBL755_2 Loadout[04].Quantity=2 Loadout[04].RackType=2BR_uk_jag Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 Loadout[07].WeaponType=TANK_NADR Loadout[07].Quantity=1 [Anti-Ship] Loadout[01].WeaponType=ALQ-101GREY Loadout[01].Quantity=1 Loadout[02].WeaponType=Phimat-UK Loadout[02].Quantity=1 Loadout[03].WeaponType=Mk22_1000_LD Loadout[03].Quantity=2 Loadout[03].RackType=2BR_uk_jag Loadout[04].WeaponType=Mk22_1000_LD Loadout[04].Quantity=2 Loadout[04].RackType=2BR_uk_jag Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 Loadout[07].WeaponType=TANK_NADR Loadout[07].Quantity=1 [FAC] Loadout[01].WeaponType=Matra-155 Loadout[01].Quantity=1 Loadout[02].WeaponType=Matra-155 Loadout[02].Quantity=1 Loadout[03].WeaponType=TANK_NADR Loadout[03].Quantity=1 Loadout[04].WeaponType=TANK_NADR Loadout[04].Quantity=1 Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 [Recon] Loadout[01].WeaponType=ALQ-101GREY Loadout[01].Quantity=1 Loadout[02].WeaponType=ALQ-101GREY Loadout[02].Quantity=1 Loadout[03].WeaponType=TANK_NADR Loadout[03].Quantity=1 Loadout[04].WeaponType=TANK_NADR Loadout[04].Quantity=1 Loadout[05].WeaponType=AIM-9L Loadout[05].Quantity=1 Loadout[06].WeaponType=AIM-9L Loadout[06].Quantity=1 Loadout[07].WeaponType=RECCE_POD Loadout[07].Quantity=1
  8. The two other F-111E squadrons at Upper Heyford (in the 20 TFW) were the 77th and 79th TFS, both of whom I visited during the 1980s. The Upper Heyford wing was also reinforced by EF-111A Ravens of (I think) the 42nd ECS from about 1984-85. The 48th TFW had the Pave Tack installation, while the 20th TFW tended to carry unguided munitions. In NATO exercises during the 1980s, the F-111Ds of the 27 TFW deployed to the UK from Cannon AFB, usually taking up residence in the HASs at A&AEE Boscombe Down, somewhat further south than the F-111E wing.
  9. The RAN would have been operating three Tribal-class destroyers during Korea, although it would have been normal practice to operate as a formation along with other Commonwealth or USN task groups. RN Light Fleet Carriers were also operating the Sea Fury off Korea at this time, and operating alongside them would have been commonplace. I just found this commentary on Commonwealth carrier ops. The RAN FAA had only been established in 1948, and HMAS Sydney operated the same form of air group as her RN sister ships, operating as an integral part of the same task groups, in between RN Carriers. Even replacement aricraft came from UK war stocks. http://www.airpower.maxwell.af.mil/airchronicles/apj/apj04/win04/hobbs.html
  10. I'm intrigued, because the RAF did not deploy entire units in Korean, only exchange pilots on secondment to the USAF and RAAF. The Fleet Air Airm *did* deploy the Hawker Sea Fury though. The frontline RAF fighters of the time would have been the Meteor F Mk 8 (used by the Aussies), the DH Vampire FB Mk 5 and, from 1952, the Venom FB Mk. 1. At the time of Korea, the RAF were more heavily engaged in their own operations in Malaya, and were stretched my meeting commitments in Europe. Delays to getting the Avon running with adequate surge margin in the Hunter meant buying in interim solutions, including the Venom, and the Canadair Sabre IV, which was deployed almost entirely with 2ATAF in West Germany. The SF2 version of the Venom FB4 is *interesting*, it has lower wing loading than the MiG-17, and, at low level, is more than capable of out-turning it. Performance in the vertical plane isn't great though. Venom vs. MiG-15 is an interesting one. The two major shortcomings of the J-47 powered Sabres were a lack of firepower (and why the USAF never fitted them with cannon is a mystery to me) and too low power/weight ratio at altitude. The Venom has the same kind of power limitations, but has a much better offensive kick with 20mm Hispanos.

  11. BAe Hawk T.1

    stephenmcparlin commented on paulopanz's file in Other

    I've had a little play with it, and it's fun to fly. A couple of simply-fixed issues though: 1. The Air-to-air and Air-to-air long range loadouts do *not* include weapons. The 30mm Aden pod can be loaded up manually though. 2. The war role for the T Mk. 1 included support for Mixed Fighter Force tactics, revolving around popping up from ground clutter to take pot shots at whatever was trying to catch up with the Tornado F Mk. 3, which was able to maintain a little distance by staying unloaded. In this role the Hawk T Mk. 1 would carry the centreline gun pod and AIM-9s on the wing pylons. One of my friends remembers doing this fondly when a student at Valley, and blagging a front-seat ride with one of the instructors on an ADEX. Apparently popping up below and behind Dutch F-16As who were otherwise engaged in trying to get close enough to a Tornado ruined their whole day. Hawk-neck, from flying at 8-9g sustained at sea level, was at one point a major issue for the aeromedical chaps. I'd expect to see the AIM-9 variant change from -9B through -9G to -9L with time. These days the T Mk 1A and T Mk. 2 tend to carry the ACMI pod for exercises.

  12. SF2 SAMs Pack

    stephenmcparlin commented on eburger68's file in Ground Object Mods

    Now trying later scenarios (UK photorealistic, 1978) with the basic Rapier installation for airfield point defence. There are three options for the launcher, plus three identically-named versions of the Blindfire radar. I'm not sure how to configure a version of an early Rapier site that works, as so far I've yet to see one launch.
  13. Intriguing. The high landing speed and structural design of the MiG-21 would make it a very difficult aircraft to land on a carrier, much less the small decks of the RN Light Fleet carriers. While the Mig-17 is a possible candidate for navalisation, and even more so the Yak-25 and it's derivatives, the first Soviet fighter that does not need long runways from the late 1950s through to the late 1960s is the MiG-23. As a point-defence interceptor, the Fishbed has very limited ability against key threat aircraft, but particularly the FAA Buccaneer fleet, which make life very difficult for any aircraft without a look-down/shoot-down system capable of engaging targets at low altitude.

  14. [Fictional] North American F-100N Sea Sabre for SF 2

    stephenmcparlin commented on ValAstur's file in What If Hangar

    Yikes! Carrier recovery will be interesting. It might also be worthwhile trying DACT with the F-8. My money will be on the F-8 under all circumstances...

  15. SF2 SAMs Pack

    stephenmcparlin commented on eburger68's file in Ground Object Mods

    I've now cracked it, although it needs a workaround. I noticed that the launchers were empty, but on 'refly'-ing the same missions, missiles appear on the launchers. I've been running a scenario involving protecting V-bomber bases against a Soviet pre-emptive strike during the Cuban Missile Crisis, and was pleased to find that Bloodhound is a real killer of incoming threat aircraft, right down to low level. Historically, there were 8 squadrons of RAF Bloodhound SAMs deployed to protect the primary V-bomber bases that ran in an arc from Finningley in the north to Marham in the south, with missile batteries deployed to cover the area behind the front-line Lightning interceptor squadrons. The Bloodhound units were essentially static, although shorter-range Army Thunderbird SAMs (which used the same radars for tracking and illumination) were also deployed as more mobile pop-up assets, probably to protect dispersed V-bomber flights at secondary airfields.

  16. SF2 SAMs Pack

    stephenmcparlin commented on eburger68's file in Ground Object Mods

    I've been trying to get the Bloodhound SAM to fit into a couple of scenarios I'm trying to model, and the associated readme points me to a WeaponData.INI file that I cannot find. Any advice on how to get a working Bloodhound battery up and running?

  17. Tornado F3 For SF2

    stephenmcparlin replied to NeverEnough's topic in Thirdwire: Strike Fighters 2 Series - File Announcements

    The 'IN RNG' symbology on the HUD appears to be constantly on. It would be useful to get a better idea of actual range for BVR engagements, particularly with the default Skyflash. Only one F Mk. 3 airframe (the Typhoon Integrated Avionics Research Aircraft) was ever fitted with kit for launching AIM-120, despite the AI Mk. 24 radar being easily capable of multiple track-while-scan performance exceeding anything except the AWG-9 and later systems on the F-14. It would be very tactically useful to get a better handle on maximum engagement ranges for SARH missiles with this radar system.
  18. OK, as an aircraft designer and performance engineer: The reference area for an aircraft will conventionally be given as the Gross Wing Area (it's extrapolated to the symmetry plane). The best open source for these will be Janes' All the World's Aircraft, which is now part of IHS. Standard reference lengths for moments will be mean aerodynamic chord (*not* geometric mean chord) for pitching moment coefficients, and span (not semi-span) for both rolling and yawing moment coefficients. The conventional way to estimate stability derivatives is to make use of the USAF Stability and Control DATCOM. The digital version is ITAR-controlled and under the care of Bill Blake at AFRL, but the paper version (not updated since 1978) is available through engineering document suppliers. You will note that DATCOM actually source most of these methods from what used to be the Royal Aeronautical Society data sheets, which are now commercially available (at some cost) from IHS ESDU. *if* you're appropriately qualified, and have computing power available, you can actually calculate/estimate aerodynamic stability and control characteristics to first order using a vortex lattice method or similar. For unswept wings, things like XFLR5 will give you a decent summary of the basic wing characteristics. It's something I'd set undergraduate aerospace engineers to do. Drag estimation is a little trickier. I have a handout I give to my students to allow them to build spreadsheet level performance models of zero-lift and lift-dependent drag for transport aircraft, but it's not really up to doing the more complex stuff you need for separated flow drag estimates on military aircraft, or the transonic/supersonic drag breakdowns you might want to consider. The Harris wave drag program that can be obtained online is a NASA version of a Boeing implementation of an RAE method from the early 1960s (Eminton's method, see ARC R&M 3221). It's reasonably accurate for slender configurations, but is crying out for a proper implementation in C or MATLAB. I'd suggest starting from the UK reports (available online through Cranfield University) rather than try to unravel the Spaghetti Fortran IV of the NASA implementation.
  19. @Toryu I once had a long conversation with an Albanian ex-fighter pilot (bizarrely enough, working in a restaurant in Farnborough). He had been current at some point on all of the Chinese-manufactured MiGs that the Albanians had operated (MiG-15UTI advanced trainer, the -17F, -19S and -21F). He rated the -19S as having the best handling characteristics of them all, which surprised me, as the sweep/aspect ratio combination is well beyond the conventional pitch-up boundary, although the big tailplane will help. I have a presentation copy of the History of TsAGI (in Russian), of which I can read a little, but it shows the development of flow control devices on swept wings in their low speed wind tunnels through the 1950s (mostly tufted models in the T-101 tunnel at Zhukovsky). It is noticeable that the MiG-19 has the largest fences know to man or beast at near mid-semispan. While these look agricultural by modern standards, it is clear from looking at these, and later models of the 57-60 degree delta wings that eventually went onto Su-9/11 and MiG-21, that the Russians in the early 1950s hadn't yet cottoned on to the potential for non-linear lift from vortex flows, which the British, French and US were beginning to exploit by the mid 1950s. They eventually twigged it, as the final versions of the delta wing aircraft had far fewer large fences than the prototypes. The MiG-19 thus represents a significant anomaly, although the only other aircraft with anywhere near the same aspect ratio/sweep combination was the Lightning, which had some lateral-directional issues in development, but was characterised by far superior handling qualities than it's Western contemporaries.
  20. The total pressure in the jet should *always* be higher than ambient at the exit, hence when running with a fully-expanded jet, there is no pressure difference across the free shear layer surrounding the jet stream. The diamond patterns in the jet efflux are caused by the reflection of shock and expansion waves until ambient pressure is reached. Nozzle pressure ratio is a key performance parameter, as the excess pressure ratio beyond unity is a measure of the residual momentum of the jet. Most of that excess pressure is converted into momentum. Kuchemann and my old colleague and neighbour, Dr Johanna Weber, worked out most of the aerodynamics of jet propulsion at Goettingen, Volkenroede and then Farnborough in the mid-1940s. There is no mechanism here for attaching files, but I produced a pdf of the relevant equations on propulsion that I provide to undergraduates doing one of my Aircraft Design Modules at universities in the UK.
  21. Afterbody drag is a big deal for most modern combat aircraft, particularly supersonically. Some are worse than others. Charlie Boppe of Grumman was particularly keen to point out that the F-14D had superior supersonic performance to the F-15, largely because the latter had a very high throttle-dependent drag and much bluffer boat-tail (corresponding to about 50% of zero-lift drag at supersonic conditions). High fuel burn at supersonic speeds was tactically limiting on the F-15, when trying to chase down Iraqi MiG-23s escaping to Iran. The F-14 and Tornado F3 were inconvenienced far less, due to their lower supersonic drag. It's also the case that relatively few fast jets actually have convergent-divergent nozzles, with most relying on a simpler, lighter convergent nozzle and accepting the thrust penalty of an underexpanded jet. The PW F100 and GE F110 engines both have these as standard, as does EJ200 on Typhoon. The F404 engine on the F/A-18A-D does not, I think. Working with a convergent nozzle implies a choked flow at, or just beyond, the nozzle exit (effectively the shear layer on the inside of the nozzle pushes the boundary out). Varying thrust then requires a higher mass flow (or rather, nozzle pressure ratio) or nozzle area. The trade-off is determined by external drag of the nozzle plus the associated mass.
  22. The aerofoil on the F-104 is actually a 3.5% thick biconvex section, which is what you get if you only have 2D design methods, which was the case before around 1954. The fuselage lift comes from development of vortex flow on the forebody, which becomes the dominant factor in the subsequent nose slice and flat spin as AoA increases. Theres an interesting comparison with the F-5 and T-38, which also have an elliptic fuselage cross-section, but with the primary axis horizontal, rather than vertical, as in the F-104. Slab-sided forward fuselages are a very bad idea for directional stabilty at higher alpha, something seen on the F-4 and F-8 as well as the F-104. The worst I've seen is actually the A-7, which has relatively less inertia about the yaw axis, so develops a spin very quickly on departure. Rule of thumb for shift in aerodynamic centre with Mach number is that it progresses from 25% mac to 50% mac between drag rise onset and the leading edge going supersonic. Because of the short chord, the physical shift in c.g. will be small. I'd estimate a static margin of about 6% for the F-104 subsonically, which implies about 31% at supersonic conditions. The F-4 did have the ability to pump fuel fore-and-aft, depending on flight condition but I don't know whether there were any comparable rules for c.g. management in the F-104. There is published SEP data for the F-4E, showing that it has a 4g STR capability at M=1.2 at the tropopause (corner point for the F-4 is supersonic). Supersonic SEP is hugely important for BVR combat, as it's a major factor in no-escape zones for head-on engagements. The F-4F was unique in losing BVR capability until the mid-life upgrade restored it. My former section head at RAE Farnborough, Dr A Jean Ross, did a very thorough analysis of the transonic nasties present on the F-4 (wing rock was possibly the most disturbing to the pilots), while Air Commodore Dave Best, former head of ETPS, was seconded to RAE to work with us when he was a young test pilot, back in the early days of Typhoon, told me many hairy stories of time on Phantoms, both as a test pilot instructor, and on operational squadrons. The supersonic manoeuvre limit on the Mirage III is, as you suggest, due to progressive lack of trimmable lift coefficient at higher Mach, although this is more due to the high static margin than loss of control power. I know that Dassault played around with relaxed stability on the Mirage 50, but I don't know if they implemented a fully longitudinally unstable FCS before the Mirage 2000.
  23. I've read the test pilot reports on all of the above... I'm actually an aircraft designer. :-) You may be able to find my AIAA White Paper on handling issues online somewhere. I'm not going to quote classified sources on an open forum, but I have read them. In the case of the F-104, the basic zero lift drag is *very* low, but the wing has a horribly low aspect ratio (subsonic lift-dependent drag) and a sharp leading edge (flow separates at very low CL). The unswept wing layout also contributes to very high lift-dependent wave drag at supersonic turn conditions. I'd suggest you read Dietrich Kuchemann's "The Aerodynamic Design of Aircraft" to get an idea of drag dependency on configuration. Other useful sources on supersonic drag include NACA reports 1284 and 1335, both by R. T. Jones. Steve Oh, and throttle-dependent drag: Base pressure is a major factor in zero-lift drag, increasingly so at supersonic Mach number. The best UNCLASSIFIED reference I can point you at is Charlie Boppe's Von Karman Institute lecture notes on Drag Estimation and Prediction, part of AGARD-R-783, which cn be downloaded from the NATO RTO website. In the case of the Javelin, the combination of a large, flat, base and the pressure drop in the base when the reheat kicked in resulted in a larger drag increment than thrust increment.
  24. The F-101 had a fairly complete collection of non-linear flight mechanics nasties. I've heard the quote "Gentlemen, we may not have invented pitch-up, but we've certainly perfected it". I've seen the NACA free-flight rocket model reports, and I concur. The Voodoo is a beast: masses of power and straight line acceleration, no significant turning ability at low speed. It's similar to the F-104 in many respects, but it's heavier and even draggier. The Vietcong and NVA used to set traps for RF-101s by stringing cables across the ends of valleys that they were known to transit in and out of the mountains to the west of Vietnam. The pilots would not be able to get enough pitch rate to escape over the ridges. Very nasty. It's notable how poor the handling qualities of most of that generation of USAF fighter aircraft were. MIL-STD-1797A came into force as a means of getting manufacturers to design with handling qualities in mind. The F-86 (and particularly the later models, with slab tailplanes) had beautiful controllability, the F-100 was a dog, and the F-101 and F-104 were totally merciless towards pilot error. The F-102 and F-106 did have nicer handling characteristics, but their complex weapons systems were let down by the Hughes Falcon being unable to hit any target smaller than Nebraska. The F-105 was better than either the F-101 or F-104 in respect of controllability, but had a high wing loading. When encountering an air-to-air threat, you used the same tactics as an F-111, point the nose towards the cows and shove the throttles forward. p.s. The only western jet I know that had even *worse* handling characteristics would have been the early models of Gloster Javelin, which had every vice under the sun plus some they'd invented specially. Indeed, the increased throttle-dependent drag when turning on the reheat system was greater than the extra thrust generated. This meant that when you pushed the throttle forward, the aircraft slowed down and the fuel gauge unwound as all that kerosene was converted to noise.
  25. The twin AIM-9 installation on the outboard pylon of the SHAR FRS Mk. 1 was not standard fit before or during the Falklands campaign in 1982. It was one of a series of improvements that were accelerated during the conflict, such as the 190 Gal external fuel tanks for the inboard pylon. Quite a lot of modifications were made at short notice, including the 'Blue Eric' jammer, installed inside a gun pod, replacing one of the ADEN cannon. It used a transmitter taken from the Vulcan, and was tuned specifically to jam the Roland systems deployed at Port Stanley. Due to lack of cooling capacity, it had a maximum run time of 30 seconds before it needed to be switched off. The initial AIM-9 fit on the Harrier GR Mk. 3 was also a rush job. Early after the conflict, two AIM-9Ls were fired by accident from a Harrier operating from a semi-prepared strip near Port Stanley, resulting in deaths on the ground. Harrier GR.3s provided air cover for a short period after hostilities, alongside a SHAR squadron on board HMS Illustrious, which made it's first commission in the South Atlantic, taking over from HMS Invincible on station. Sea Harriers of 809 NAS and Harriers of 1 Sqn, RAF went south as part of the second wave of ships, on board the Atlantic Conveyor, or, in some cases, made direct flights from Ascension island with tanker support, recovering directly onto HMS Hermes.
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