Suggestion for a chargeable MiG21bis II upgrade

[303_Kermit]

7 hours ago, Bremspropeller said:

The FL should also be able to carry the GP-9, correct?

Of course. There are lots of photos and reports from combat deployment. Interesting fact: When Egypt and Syria bought first series of FL, GP-9 was already developed, and had proved its value. In spite of these arab FL's were ordered without them.

@WinterH
As for our (and there's a lot of us) "Pointless Vietnam dreams" - VPAF used F-13, PF, PFM and MF variant of MiG 21. Those (plus FL) are also the versions that took part in almost every conflict in 1960-1980. DCS without them is... Incomplete.

Edited February 23, 2023 by 303_Kermit

[Dragon1-1]

There's also the fact that the F-13 is, by far, the prettiest MiG-21 of the bunch.  Nice, clean and lightweight, what more do you want? Sure, it's not the most modern, but it'll kick a Phantom's ass in a dogfight, and it's both faster and has better radar than MiG-19. The bis looks fat compared to it.

[some1]

Looks are deceiving. What F-13 looses in weight, it also looses in thrust, and I'm not even counting emergency reheat on the BIS. It won't be much better dogfighter. 

Plus it only gets two R-3 missiles and a single gun with tiny amount of ammo. 

[Bremspropeller]

1 hour ago, some1 said:

Looks are deceiving. What F-13 looses in weight, it also looses in thrust, and I'm not even counting emergency reheat on the BIS. It won't be much better dogfighter. 

With lower weight comes lower AoA required for the same ITR and STR, hence less drag to be overcome by less thrust.

The F-13 is widely known for it's best dogfighting capabilities in the whole -21 family by most pilots flying a variety of models, yet not much else. It's already short on fuel when retracting the landing-gear on take-off, it has to rely on GCI and it's combat value is very limited. It's a hell of an aircraft to fly, look at and have fun with, though.

It's a MiG-19 with cooler shades on.

I think there should be at least one Fishbed out of each generation: One F-13/J-7, one PFM, one MF and the Bis we already have. The two-seaters are also very cool jets and one of those should be useable somewhat as a contemporary to the upcoming Mirage F1BE.

With those aircraft, you'll cover 80% of all redfor cold war jets. That's ballpark, so don't quote me on that. I'm not looking at WP air forces here, but mostly third-world tropical paradises with charming young presidents in tailored suits, which is what is a lot more interesting to me than all the Central Europe "Fulda Gap not going nuclear within 3 minutes" pipedreams.

[portman]

vor 2 Stunden schrieb Dragon1-1:

There's also the fact that the F-13 is .... both faster and has better radar than MiG-19.

The F-13 has no radar at all, only a radio range finder.

[some1]

1 hour ago, Bremspropeller said:

With lower weight comes lower AoA required for the same ITR and STR, hence less drag to be overcome by less thrust.

Yeah, but we're looking at an empty weight difference of about 500 kg (roughly 10%). It won't be night and day. MTOW is much higher, but that's just stuff - fuel and payload. Do not load full tanks on the Bis, set 1/3rd of gun ammo and two R-3S, and you get a rough approximation of what F-13 could do. 

That being said, I'd still love to see F-13 in game, although I would prefer an early PFM with the old style one-piece canopy. 

[Bremspropeller]

I do think that ~10% is quite a bit, depending onthe situation. Also, don't forget about the slightly better view outside the F-13 and that it most likely has a little less drag.

The main drawbacks should be the low combat-capability (weapons and radar) and the low fuel-load.

16 minutes ago, some1 said:

That being said, I'd still love to see F-13 in game, although I would prefer an early PFM with the old style one-piece canopy. 

Isn't that a PFS?

The PFx are so confusing as there's a hodge-podge of versions and sub-variants that are impossible to externally distinguish.

[some1]

To my knowledge, the change to the new ejection seat that required two-part canopy happened mid production, so both PFS and PFM's existed with one or another. And they are outwardly so similar even the Soviets mixed them up. 

[Ala13_ManOWar]

Do any of you recall that interview with a former Finish MiG-21 pilot on YT? He clearly stated performance was overall the same, more thrust but more weight also, hence about the same after all, but he also stated he preferred the F-13 all the way over the Bis. That has to mean something coming from someone who flew them both mates .

[303_Kermit]

4 hours ago, Bremspropeller said:

The F-13 is widely known for it's best dogfighting capabilities in the whole -21 family

PF/PFM with very similar weight, possess much bigger thrust. Except of bis those two possess best t/w ratio, out of MiG-21 family. On medium and high altitudes (above 4000m) , where 2-nd stage AFB of Bis isn't working PF,PFM, F-13 has better T/W ratio.

Edited February 27, 2023 by 303_Kermit

[Bremspropeller]

I seem to remember reading somewhere that some F-13s also recieved the R11F2-300 motor as a retrofit.

Do you know if that is correct?  Must have been an export-customer - probably in the Middle East or maybe India. Might even have been the EGAF, don't know anymore. 

[Dragon1-1]

9 hours ago, portman said:

The F-13 has no radar at all, only a radio range finder.

It's a radar gunsight, just like in the MiG-17 and F-86. It can also range the target for missile launch, which is all you need. Sure, it doesn't have the radar screen, but the MiG-19's radar isn't very useful for searching, either (by the time you see the target on radar, you can usually see it visually, too). The MiG-21F-13 was a GCI-bound day fighter, the idea at the time was that those don't really need a search radar. 

[303_Kermit]

4 minutes ago, Dragon1-1 said:

but the MiG-19's radar isn't very useful for searching, either (by the time you see the target on radar, you can usually see it visually, too)

Night operations. MiG-19 wasn't constructed for DCS Dogfight servers, where it's always sunshine and bright sunny day.

[Bozon]

19 hours ago, Dragon1-1 said:

There's also the fact that the F-13 is, by far, the prettiest MiG-21 of the bunch.  Nice, clean and lightweight, what more do you want? Sure, it's not the most modern, but it'll kick a Phantom's ass in a dogfight, and it's both faster and has better radar than MiG-19. The bis looks fat compared to it.

I disagree and I like the hump on the back of the Bis - makes it look meaner. It’s a different kind of pretty…

I also like the humped back A-4 Skyhawks better than the early version, just personal taste.

[Кош]

10 часов назад, Dragon1-1 сказал:

don't really need a search radar. 

More like they had to conserve weight to reach requested altitudes. As engine power increased and radar mass decreased they jumped on it immediately with P and S versions. It wasn't guaranteed that a war would ever start, but those recon aircraft, balloons and other cold war spy mess was a daily reality and needed immediate solutions.

Edited February 28, 2023 by Кош

[Hiromachi]

On 2/23/2023 at 12:13 PM, Bremspropeller said:

Or the really lack thereof. The PFM at least has the improved radar and the gunpod.

PF gets all the same capabilities as the PFM, bar the BLC (SPS) installation and radio altimeter.

[Hiromachi]

23 hours ago, Bremspropeller said:

The F-13 is widely known for it's best dogfighting capabilities in the whole -21 family by most pilots flying a variety of models, yet not much else. It's already short on fuel when retracting the landing-gear on take-off, it has to rely on GCI and it's combat value is very limited. It's a hell of an aircraft to fly, look at and have fun with, though.

We've been there in October. Opinions about F-13 vary: 

 

22 hours ago, some1 said:

Yeah, but we're looking at an empty weight difference of about 500 kg (roughly 10%). It won't be night and day. MTOW is much higher, but that's just stuff - fuel and payload. Do not load full tanks on the Bis, set 1/3rd of gun ammo and two R-3S, and you get a rough approximation of what F-13 could do. 

That being said, I'd still love to see F-13 in game, although I would prefer an early PFM with the old style one-piece canopy. 

F-13 take-off weight (two R-3S missiles) - 7370 kg, near empty weight (landing with 7% of fuel remaining and no missiles) - 5217 kg,

PF take-off weight (two R-3S missiles) - 7838 kg, near empty weight (landing with 7% of fuel remaining and no missiles) - 5573 kg,

Bis take-off weight (two R-3S missiles) - 8726 kg, near empty weight (landing with 25% of fuel remaining and no missiles) - 6800 kg. There is no 7% fuel equivalent in the book, but considering that total internal fuel weight is around 2400 kg, 7% would be around 6368 kg.

This is based on the available manuals. Thats like ~20% (Take-off) to 22% (Landing), not 10%. But note that 7% fuel for the Bis is sub-optimal for landing configuration, changing landing characteristics.

Either way its twice as much as you think.

 

[Dragon1-1]

The bis is thick, fat and humpy.  The F-13 is long and sleek, a truly beautiful machine. As good as the bis can be in vertical, it's the older versions that can really turn. Sure, avionics are sparse, but it doesn't need computers to kick ass.   

[Bremspropeller]

1 hour ago, Hiromachi said:

PF gets all the same capabilities as the PFM, bar the BLC (SPS) installation and radio altimeter.

That's an interesting GP-9 retrofit on the PF!

According to Y.Gordon, the PFM during ongoing production got the improved RP-21M radar. It's not clear, however, what the impovement was.

 

[some1]

1 hour ago, Hiromachi said:

F-13 take-off weight (two R-3S missiles) - 7370 kg, near empty weight (landing with 7% of fuel remaining and no missiles) - 5217 kg,

Bis take-off weight (two R-3S missiles) - 8726 kg, near empty weight (landing with 25% of fuel remaining and no missiles) - 6800 kg. There is no 7% fuel equivalent in the book, but considering that total internal fuel weight is around 2400 kg, 7% would be around 6368 kg.

Something looks off in your numbers, the Bis lost 2358 kg between takeoff and landing at 7% fuel, while F-13 lost 2153. Minus 150 kg missiles, that is 2200 vs 2000 in consumables, fuel mostly. Only 200 kg difference.

Yet the difference in fuel capacity between the planes is around 400-700 kg depending on the particular F-13 s/n, not 200 kg.

Yefim Gordon gives empty weight for F-13 at 4870 kg, while for Bis he quotes 5340. Takeoff 7100 vs 8750 respectively. As I said, it looks like the difference in fuel and payload makes the most of it, not the airframes themselves. 

 

[Hiromachi]

51 minutes ago, Bremspropeller said:

That's an interesting GP-9 retrofit on the PF!

According to Y.Gordon, the PFM during ongoing production got the improved RP-21M radar. It's not clear, however, what the impovement was.

Both PF and PFM had the RP-21M, but in regards to the former one, it was introduced later in the production or during major overhaul. 

I have somewhere a list of modifications. Or I can just go through manuals and see if I can observe differences in description.

48 minutes ago, some1 said:

Something looks off in your numbers, the Bis lost 2358 kg between takeoff and landing at 7% fuel, while F-13 lost 2153. Minus 150 kg missiles, that is 2200 vs 2000 in consumables, fuel mostly. Only 200 kg difference.

Yet the difference in fuel capacity between the planes is around 400-700 kg depending on the particular F-13 s/n, not 200 kg.

Yefim Gordon gives empty weight for F-13 at 4870 kg, while for Bis he quotes 5340. Takeoff 7100 vs 8750 respectively. As I said, it looks like the difference in fuel and payload makes the most of it, not the airframes themselves. 

Nothing can be off beyond the extrapolation of the weight at landing with 7% fuel since specific number is listed only for 25% remaining fuel (6800 kg).  

If you don't like the numbers, you can take it with Mikoyan OKB:

Internal fuel weight in the bis is 2400 kg, in the F-13 its 2080 kg, so 320 kg.

[some1]

25 minutes ago, Hiromachi said:

Internal fuel weight in the bis is 2400 kg, in the F-13 its 2080 kg, so 320 kg.

Fair point, looks like Gordon's book has some incorrect weight numbers, or taken for a different aircraft version.

[303_Kermit]

2 hours ago, some1 said:

Gordon's book has some incorrect weight numbers, or taken for a different aircraft version.

As usual... I got his books about MiG-23 and Phantom II. Both possess nice "Easter Eggs"

[Hiromachi]

16 hours ago, Bremspropeller said:

According to Y.Gordon, the PFM during ongoing production got the improved RP-21M radar. It's not clear, however, what the impovement was.

So quick overview of the manuals indicated to me only one major difference, in that RP-21M is also capable of detecting, intercepting and automatically tracking a target under pulsed non-synchronous interference conditions ( 1. Asynchrone Impulsstörungen - http://www.mig-21-online.de/mig-21/funkmessvisier/abfangen-fm-stoerungen/) and under conditions where passive interference dipoles ( 2. Chaff) are released toward the interceptor aircraft:

1.

2. 

There are probably more differences, but it seems RP-21 to RP-21M upgrade focused on filtering ECM.

[Bremspropeller]

Great info, thanks Hiro!