NeilWillis Posted February 12, 2016 Posted February 12, 2016 I thought the Lightning was made by the English Electric company, not BEA? BEA came after AFAIK. BEA - British European Airways - never built a single airframe. BAE - British Aerospace Engineering - originally a government instituted amalgamation of EE and many other companies involved in the aerospace industry in the UK. English Electric - Famous for making washing machines - oh and the Lightning - Apparently their tumble driers fitted with afterburners were not quite such a success story!
Hummingbird Posted February 12, 2016 Author Posted February 12, 2016 Interesting - had to pull out the NATOPS to double check this. The LEFs had three manual positions that could be selected by the pilot with the incidence wing in the down position as above. So the first photos look like Cruise droop position (~6 degree down inner) , the last would be in the clean position (no droop), and there was also a spin droop position (~36 degree down inner). Yes, the cruise droop was used during dogfights, activated by the flip of a switch on the control collumn, and apparently proved useful when trying to a get a lead on maneuvering MiG-17's in Vietnam.
Hummingbird Posted February 12, 2016 Author Posted February 12, 2016 Another thing: The MiG-21variant most numerous during the Vietnam war was as far as I can tell considerably heavier than the F-13 tested by the Americans. This is something which will have a significant effect on the MiG-21's observed advantage in ITR, the F-13 being quite impressive there due to its 50-55 psf wing loading.
Basher54321 Posted February 12, 2016 Posted February 12, 2016 The VPAF used these variants 66 to 72: Trainer: MiG-21U MiG-21US MiG-21UM Fighter: MiG-21F-13 from Jan 66 MiG-21PF (PFL / PFV) from April 66 MiG-21PFM MiG-21MF from 69? Have recently got a more complete F-8H manual that gives some more info on cruise droop:
Hummingbird Posted February 12, 2016 Author Posted February 12, 2016 The VPAF used these variants 66 to 72: Trainer: MiG-21U MiG-21US MiG-21UM Fighter: MiG-21F-13 from Jan 66 MiG-21PF (PFL / PFV) from April 66 MiG-21PFM MiG-21MF from 69? AFAIK the PF & PFM featured a 1400 kg higher empty weight than the F-13, which is significant, and the loaded weight difference was even higher. I suspect that the ITR of a combat loaded MiG-21PFM in that case would be very similar to the F-8E, if not worse. That having been said the MiG-21's initial pitch rate was likely higher thanks to the Delta wing. Whilst talking about pitch rate the EE Lightning supposedly featured an extremely high one, as evident when watching the impressive pitch up performed just after take off during the airshows back in the day. Have recently got a more complete F-8H manual that gives some more info on cruise droop: Yeah that's what I read as well, which meant that it was used in basically any form of turn fight. The F-8's best turning speed according to one pilot was 350 KIAS at a combat wing loading of 60-65 psf.
Hummingbird Posted February 12, 2016 Author Posted February 12, 2016 A good video on the Lightning: dTr2UvLqfkQ The maneuverability it displays is quite amazing for a fighter of that era. I've certainly never seen a MiG-21 pull off such stunts.
Basher54321 Posted February 12, 2016 Posted February 12, 2016 Empty Weights: NAVAIR / SAC F-8C 16,483 lbs (1967) F-8D 17,541 lbs (1967) F-8E 17,836 lbs (1967) F-8J 19,815 lbs (1973) Less certain on the 21 - only have a Bis manual in English (A.Mladenov , MiG-21, 2014) (includes a PFM Russian manual as source) MiG-21F-13 10,602 lbs MiG-21PFM 11,843 lbs MiG-21MF 11,770 lbs (Y.Gordon , MiG-21, 2008 ) MiG-21F-13 10,738 lbs MiG-21PFM n/a MiG-21MF 11,790 lbs
Hummingbird Posted February 13, 2016 Author Posted February 13, 2016 The ultimate Crusader apparently was the F-8J which featured "significantly increased wing lift due to greater slat and flap deflection and the addition of a boundary layer control system & enlarged stabilators"
Basher54321 Posted February 13, 2016 Posted February 13, 2016 The BLC seems to have been controversial between the vets when the J went to SEA. It had been tested in colder air - but there wasn't enough excess thrust to provide safe landing handling (which was the general point). Seems the J57-P-420 wasn't in the first Js and that seemed to improve things along with a reduction in bleed air. Interesting to see the SAC documents list drop tanks as part of the stores - I don't think I have ever seen a photo with them being carried.
Hummingbird Posted February 13, 2016 Author Posted February 13, 2016 Yeah as your figures show the J also suffered quite a weight increase on top, so perhaps the gains were minimal. Looking through the HaveDoughnut report the F-8E was able to sustain a higher G load than the MiG, and the ITR was close despite the extremely low 50 psf wing loading of the MiG-21 F-13. The F-4E was also close, which was evident in some of the later tests conducted. In the end I can't imagine the increased thrust of the PFM & MF making up for a ~50% increase in wing loading over the F-13. In other words fully loaded I'd expect a marked decrease in STR and esp. ITR between these two types, more than enough to give the F-8E the advantage in both ITR and STR.
Hummingbird Posted February 21, 2016 Author Posted February 21, 2016 Alright extracted the ITR figures for the F-8E at 30,000 ft (9,144 m) at a wing loading of 78 psf: Mach / ~G 0.4 / 1.1 0.5 / 2.0 0.6 / 2.5 0.7 / 3.2 0.8 / 4.4 0.9 / 5.8 1.0 / 7.6
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