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Old 01-25-2020, 09:57 PM   #321
TLTeo
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Are you sure the F8 could pull no more than 6.5Gs? Even the F-104 could do 7.5 (granted, only at Mach ~0.9, but still).
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Old 01-25-2020, 10:27 PM   #322
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Structural limit stipulated in manual is 6.4 G symmetrical and 5.2 for rolling pullout. But this limit is only limit. I have a 1973 Field Technical Report from NAS Miramar related to F-8J cumulative accelerations and fatigue life, indicating a few dozens of accelerations of more than 7 Gs. Continuous high loads on the wings were having various effects, most often cracks or deformations. But no wing failure is recorded. I'm pretty sure ultimate load factor is quite a bit higher than 6.4 G.
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Old 01-26-2020, 08:06 AM   #323
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Quote:
Originally Posted by SgtPappy View Post
Also I am not too sure where you found the MiG-21bis to pull more than 8G sustained on special burner. My diagram says at sea level, it only reaches around 7.25G with special burner at 7500 kg (best I could find). I can't imagine 2x R-3S's would make such a massive difference:
I have found the chart through google in an old post on this forum: https://forums.eagle.ru/showpost.php...46&postcount=7

However you can also find it in other languages, but never the full document it belongs to.

What I find interesting is, that your chart is again different than the one from the English MiG-21bis manual, which I had used for my chart. Your German chart is showing higher g in full AB, than the English does for emergency AB.
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Old 01-26-2020, 08:55 AM   #324
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This comes from Polish MiG-21bis Flight Characterics doc. It gives various characteristics such as max acceleration depending on ARU "arm", burner (either with 2nd stage called "CzR" or without), weight (amount of fuel left) and load (with two R-3S missiles).
This should give better comparison Jonne:
Spoiler:






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Old 01-26-2020, 01:15 PM   #325
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Thank you Hiromachi! That will give some data.
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Old 01-26-2020, 05:53 PM   #326
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Quote:
Originally Posted by Jonne View Post
I have found the chart through google in an old post on this forum: https://forums.eagle.ru/showpost.php...46&postcount=7

However you can also find it in other languages, but never the full document it belongs to.

What I find interesting is, that your chart is again different than the one from the English MiG-21bis manual, which I had used for my chart. Your German chart is showing higher g in full AB, than the English does for emergency AB.
Very strange indeed - the one the Hiromachi provided is another one that I have. Intuitively, I it seems more realistic given the other planes' performance figures at the time.

What do you guys think about all these plots? Which ones should we trust? I had not realized there was so much conflicting data.
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