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MiG-21 performance data missing


MikeMikeJuliet

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Hello, everyone.

 

I've been studying the MiG-21 for a bit now and I'm in process of creating a "cheat sheet" for the most important numbers, limitations and weight calculations.

 

But there are a number of things missing from the manual regarding the aircraft's performance.

Namely:

IAS/TAS/Mach speed for maximum climb angle,

IAS/TAS/Mach speed for maximum climb rate with 100%, AFB and CSR

IAS/TAS/Mach speed for fuel efficient climb

Corner speed and ITR in degrees/second

Speed for max STR, and STR in degrees/second

Speed of minimum turn radius

Maximum required landing run

 

and additionally, if someone knows (though I can test these easily)

Minimum required altitude AGL for pure vertical maneuvering (namely split-S).

 

Has anyone done research on these that they are willing to share? Might there be documents about this available?

 

 

Regards,

MikeMikeJuliet

DCS Finland | SF squadron

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www.checksix-fr.com/downloads/falcon4/Topolo/zip/Project-21/NATOPS_FLIGHT_MANUAL-Mig-21bis.pdf

 

found here

 

But I personally take this addito salis grano because of the huge FM changes occurred recently. There may be significant differences with the current simulation.

I'll buy :

МиГ-23МЛД & МЛА МиГ-27К МиГ-25 Mirage III F-4E any IJ plane 1950' Korea Dynamic campaign module

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Climb angle is not something which would be covered by pilot's manual. Energy analysis suggests maximum constant angle is in the M0.7 region but is relatively flat in the 0.3-0.9M region.

 

Tactical airplanes usually specify minimum time to altitude which in the MiG is 950-980 TAS (depending drag). The conversion to supersonic happening at 10-11km before continuing climb after 1200 IAS at M1.8-1.9.

 

Minimum fuel to climb (for range) is AB to 600 then MIL to 850-870 TAS until about 10km height when 530 km/h is the speed attained by MIL. The cruising economy IAS decreases with gross weight.

 

Maximum ITR is attained at about 400 IAS, 8g, SL of 22 dps.

 

Maximum STR is attained SL, 420 IAS, 4.6g, 12 dps.

 

Minimum ST radius SL, 310 IAS, 3.4g of about 900m.

 

In standard case (6800kg, chute, ISA, no wind) minimum landing roll requires 600m actual with 1350m runway length.

 

In the acrobatics section the half loop (descending) from 450 IAS requires no less than 2500m.

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Thankyou for the answers!

 

I am a bit surprised that the max ITR and STR are attained at such a low speed. One would expect that being so close to the evolutive speed, and below the 600 km/h mark (above fly with g, below with aoa) that the aircraft would not be able to hold speed. Then again, as speed increases same G increases turn circle eventually increasing turn rate... and the STR is attained at a relatively low G.

 

Interesting.

 

Regards,

MikeMikeJuliet

DCS Finland | SF squadron

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Climb angle is not something which would be covered by pilot's manual. Energy analysis suggests maximum constant angle is in the M0.7 region but is relatively flat in the 0.3-0.9M region.

 

Tactical airplanes usually specify minimum time to altitude which in the MiG is 950-980 TAS (depending drag). The conversion to supersonic happening at 10-11km before continuing climb after 1200 IAS at M1.8-1.9.

 

Minimum fuel to climb (for range) is AB to 600 then MIL to 850-870 TAS until about 10km height when 530 km/h is the speed attained by MIL. The cruising economy IAS decreases with gross weight.

 

Maximum ITR is attained at about 400 IAS, 8g, SL of 22 dps.

 

Maximum STR is attained SL, 420 IAS, 4.6g, 12 dps.

 

Minimum ST radius SL, 310 IAS, 3.4g of about 900m.

 

In standard case (6800kg, chute, ISA, no wind) minimum landing roll requires 600m actual with 1350m runway length.

 

In the acrobatics section the half loop (descending) from 450 IAS requires no less than 2500m.

 

Just to confirm, were the values on your post in knots or in kilometers per hour? Going by the document BogeyJammer posted, those values are quite close in KCAS.

 

If this is the case, then no wonder I had a feeling the speeds were a bit low :D

DCS Finland | SF squadron

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Yes, turning in KCAS. I wasn't reading the bottom of the chart too closely. The TASes for climb and IASes for cruise are in km/h.

 

Max STR at ~5-6g is quite common (e.g. F-16). Although when I look a second time I see MaxSTR at 14 dps 460 KCAS 6g. I must have been looking at the 5,000' chart.

 

And that MaxITR of 22 dps violates the 28 alpha rule. Conforming to 28 alpha maximum MaxITR is lower at 18 dps 465 KCAS.

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