Alternate tank-busters and other aircraft

I've managed to derail another thread, so here it goes here - on alternate tank-busting and other aircraft.

In terms of layout maybe, but the structure could not handle it:
https://wiki.warthunder.com/index.php?title=LaGG-3-34

You will note that NS 37 cannon was not proposed for Bf 109, the MK 101 was.

That was with an engine that was 1260 hp, not 1000hp of the 100 octane HS 12Y suggested.
https://en.wikipedia.org/wiki/Lavoc...ations_LaGG-3_.28data_for_LaGG-3_series_66.29
The HS 12Y would have sub-1000hp without 100 octane fuel, so at least 300hp or more weaker than the Soviet engine, which was already under powered for the LaGG 3 with the cannon.
https://en.wikipedia.org/wiki/Lavoc...ations_LaGG-3_.28data_for_LaGG-3_series_66.29

Lagg-3-37 was at 2832 kg empty, 3363 kg ready for take off (per Khazanov & Yefimov book on Soviet fighters, the tables from that book are floating on the 'net). 'Usual' Lagg-3 were at ~3300 kg ready for take off (bar a few lightened examples), so the weight increase due to change in armament was negligible.
The Bf 109F1/F2 were at 2248 kg empty, 2728 kg ready for take off (no racks, no bomb/drop tank; Kennblatt ). Suplanting HS 12Y (late marque) vs. DB 601N decreaces weight by ~120 kg just on bare engine. Change from MG 151/15 to MK 101 (bare cannons 42 vs. 139 kg) adds almost 90 kg. Net result - weight drop by 30 kg. Not much, but no increase.
In 1941, there is no VK-105PF engine, but M-105P. Apart from change in nomenclature, the PF engine was heavier and alloved for greater boost - hence the 1260 HP power figure, unlike the 1000-1100 HP for the M-105P.
Lagg-3 is draggier than 109F (10% bigger wing, thicker both in relative and absolute terms) and 20% heavier.
How good was the Bf 109F on 1000 PS? With actually 1020 PS (= DB 601N on 30 min power), it was doing 495 km/h on deck, with 1050 PS it was good for 595 km/h at 5 km. Granted, no HS 12Y of 1940/41 will provide 1050 PS at 5 km. The Yak 1 was thereabout at sea level, the Lagg-3 was at ~475 km/h at SL.
 

Driftless

Donor
How about handwaving the US early mis-fires (pun intended) with 20mm guns and give the P-47 4x20mm's Hispano's? Or as long as I'm in full conductor mode on hand-waving problems away; the perpetual pre-war favorite 4x23mm Madsen's?
 

Deleted member 1487

For the HS12Y Bf109 we are probably looking at around 900hp max take off with 87 octane fuel, limited altitude performance (not a big issue with ground attack aircraft), and a 139kg, 10 round magazine cannon that may or may not fit (the Soviet engine and HS 12Y were different sizes, not to mention it was different than the DB601N too), and a major potential structural issue during firing like the heavier LaGG3.
The DB601N is taller and thinner, the lengths are about the same. Plus we don't know if the fuselage can actually fit the MK101, nor handle it's recoil. It will have a significant deficit in speed and maneuverability if it can and only 10 rounds. Not sure where the 30 round box magazine of later versions would even fit. Remember IOTL they couldn't get the MK103 to work in the Bf109G and the MK103 was less powerful and lighter than the MK101, plus used electrical firing instead of mechanical:
https://en.wikipedia.org/wiki/MK_103_cannon
The original specification for the MK 103 called for it to fit inside an aircraft's engine mounting (possibly as a Motorkanone, firing through a hollow propeller hub), however, it proved to be too large and heavy to fit into small fighters like the Bf 109.

http://www.kurfurst.org/Engine/DB60x/DB601_datasheets_N.html
https://en.wikipedia.org/wiki/Hispano-Suiza_12Y#Specifications_.2812Ycrs.29
 
The MK 101 was at 139 kg without ammo magazine/drum. With full 30 round drum it was at 185 kg. I'm not sure that 10 rd magazine was ever available for the MK 101 (might be - lack of evidence does not mean there is no evidence), the 6 rd magazine and 30 rd drum are listed in the manual for the MK 101. The MK 103 was at 145 kg, bare gun. Manuals for those wepons, as well as other German technicalities are available for download at the excellent site.
For the n-th time, I've make no suggestion of DB-powered 109 tank-buster with MK 101/103.
Re. recoil: the ammo for MK 101 will have recoil impuls equal to perhaps of 60% of the NS 37 (500g @ 725 m/s vs. 745g @ 880 m/s), that will be further reduced due to the muzzle brake, that NS-37 was without.

The tank-buster Bf 109 can go hunting Il-2, unlike the other German tank-busters like the versions of the Ju 87 or Hs 129, while not being afraid of Soviet fighters. Or other Allied fighters, bar Spitfire LF or stripped P-39.
 

Deleted member 1487

The MK 101 was at 139 kg without ammo magazine/drum. With full 30 round drum it was at 185 kg. I'm not sure that 10 rd magazine was ever available for the MK 101 (might be - lack of evidence does not mean there is no evidence), the 6 rd magazine and 30 rd drum are listed in the manual for the MK 101. The MK 103 was at 145 kg, bare gun. Manuals for those wepons, as well as other German technicalities are available for download at the excellent site.
Ok, so even heavier than I thought.

For the n-th time, I've make no suggestion of DB-powered 109 tank-buster with MK 101/103.
Didn't say you did, just that they tried to make it work and the gun was just too big, too heavy, and too powerful to fit in the Me109. The HS12Y is fatter and shorter, but the same length, so you're not getting much more space, even with a minor weight savings, while losing a lot of horsepower.

Re. recoil: the ammo for MK 101 will have recoil impuls equal to perhaps of 60% of the NS 37 (500g @ 725 m/s vs. 745g @ 880 m/s), that will be further reduced due to the muzzle brake, that NS-37 was without.
Ok and IOTL they couldn't get the MK103 to fit in the Me109. A lighter, much less powerful engine isn't going to change the fact that the airframe can't take it.

The tank-buster Bf 109 can go hunting Il-2, unlike the other German tank-busters like the versions of the Ju 87 or Hs 129, while not being afraid of Soviet fighters. Or other Allied fighters, bar Spitfire LF or stripped P-39.
The 20mm Bf109 was able to kill the IL-2 just fine, Erich Hartmann did it repeatedly. Despite being armored against ground fire it was not set up to handle attacks from above and behind. A heavily underpowered Bf109 with a big heavy gun in the nose is going to be more scared of fighters than even the Jabo FW190.
 
How about handwaving the US early mis-fires (pun intended) with 20mm guns and give the P-47 4x20mm's Hispano's? Or as long as I'm in full conductor mode on hand-waving problems away; the perpetual pre-war favorite 4x23mm Madsen's?
Although it doesn't seem to generate much babble, the thickness of the P-47 wing is barely perfect at the job of containing the 8 .50s that it was designed for, and substituting Hispanos would require the use of "boils", beules, blisters, or fairings of some unsightly sort. The Republic S3 airfoil seems to have an 11:1 thickness/chord ratio, applied root to tip. Speaking of the Madsen, did you know that danish aren't Danish? That's probably why I have a danish, but nobody ever got Madsens.
 
Ok and IOTL they couldn't get the MK103 to fit in the Me109. A lighter, much less powerful engine isn't going to change the fact that the airframe can't take it.

Aparently you don't get it that it was engine, not fuselage, that was precluding installtion of a big gun as-is on the Bf 109. Elusive is also the thing that Hartman killed no tanks with his Bf 109.

At any rate, here goes the nex proposal. Say that RLM/LW buys the Fw 187. It might serve as a base for general-purpose high performance fighter bomber, with a cannon under centreline for AT work. If radial-powered version is required, the G&R 14N should be an unproblematic fit.
 
The major what-if would've been the non-existence of RR Peregrine, so Westland has Whirlwind designed around Merlins.

Criticising Hartmann for not killing tanks is a bit like complaining that Gerd Müller didn't save many penalties.

I'm not criticising him, it was not him who was responsible for hardware.
 

Deleted member 1487

Aparently you don't get it that it was engine, not fuselage, that was precluding installtion of a big gun as-is on the Bf 109. Elusive is also the thing that Hartman killed no tanks with his Bf 109.
You haven't provided a source that says the DB engine was the problem, the link I posted said it was the fuselage being too small and the gun too big that was the problem. You're also moving the goal post; you said that IL-2 killing was a role that needed filling, it wasn't an issue because IOTL fighters shot down plenty with standard 20mm.

At any rate, here goes the nex proposal. Say that RLM/LW buys the Fw 187. It might serve as a base for general-purpose high performance fighter bomber, with a cannon under centreline for AT work. If radial-powered version is required, the G&R 14N should be an unproblematic fit.
Since the Bf110 did that job with the Mk 101 with a belly gondola IOTL the Fw187 could too with air breaks.
Perhaps the Germans could produce the GR or have the French do it with supervision (there was a lot of sabotage in factories), but again with the Hs129 the the unarmored wing engines would be highly vulnerable, even the radial engine without the fuselage to protect it. The Hs129 was dropped repeatedly with rifle caliber bullets. Still, better than nothing if there aren't enough DBs or equivalent engines. But then the Bf110 was already plenty for that fighter-bomber role, why double up with the Fw187? There were plenty of DBs to go around in 1941 for Bf110 use.
 
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Driftless

Donor
Speaking of the Madsen, did you know that danish aren't Danish? That's probably why I have a danish, but nobody ever got Madsens.
You got me to look that up.... The "danish pastry" originated in Austria, before becoming popular in Denmark. The Scandinavians refer to them as "Viennese bread". You learn something new everyday if you aren't careful.
 
You haven't provided a source that says the DB engine was the problem, the link I posted said it was the fuselage being too small and the gun too big that was the problem. You're also moving the goal post; you said that IL-2 killing was a role that needed filling, it wasn't an issue because IOTL fighters shot down plenty with standard 20mm.

A cannon, here the HS 404 (252 cm long) within the engine's Vee; intake manifols located outboard the Vee free the volume of interest: link
The Vee filled with 'plumbing', fuel injection pump etc. on the DB 605 precluded installation of a cannon that has gas return port at the barrel. Diameter of the blast tube for the perspective motor-kannone on the DB 605 was 70mm, thus allowing only 80 cm of the barrel of the MK 103 to fit, leaving the rest 2/3rds of the cannon's length to stick behind the engine. The MK 103M was a major redesign, with change/relocation of gas porting, thus making the barrel free from piping at it's half length, in order for cannon to fit to the Bf 109. Source: 'Rapid Fire', book by Tony Williams, pg. 168
The MK 103M was to be installed on the Bf 109K-8, K-10 and K-14, but war ended that plan obviously. link
Re. killing the Il-2: I'm not moving the goal post. This is what a Bf 109 with big cannon could've done, apart from killing tanks. Unlike what could the Stuka of Hs 123 or Hs 129.


Since the Bf110 did that job with the Mk 101 with a belly gondola IOTL the Fw187 could too with air breaks.
Perhaps the Germans could produce the GR or have the French do it with supervision (there was a lot of sabotage in factories), but again with the Hs129 the the unarmored wing engines would be highly vulnerable, even the radial engine without the fuselage to protect it. The Hs129 was dropped repeatedly with rifle caliber bullets. Still, better than nothing if there aren't enough DBs or equivalent engines. But then the Bf110 was already plenty for that fighter-bomber role, why double up with the Fw187? There were plenty of DBs to go around in 1941 for Bf110 use.

The Fw 187 with same engines as Bf 110 will be a better performing A/C. In presence of Allied fighters the Bf 110 was not in favorable position.

edit: the monthly production of DB 601 engines was barely greater in 1941 than it was in 1940, around 500 pcs. The production of Jumo 211 engines incresed from ~500 in mid 1940 to more than 1000 by May of 1941, with further slow increase in rest of 1941.
 
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Deleted member 1487

A cannon, here the HS 404 (252 cm long) within the engine's Vee; intake manifols located outboard the Vee free the volume of interest: link
The Vee filled with 'plumbing', fuel injection pump etc. on the DB 605 precluded installation of a cannon that has gas return port at the barrel. Diameter of the blast tube for the perspective motor-kannone on the DB 605 was 70mm, thus allowing only 80 cm of the barrel of the MK 103 to fit, leaving the rest 2/3rds of the cannon's length to stick behind the engine. The MK 103M was a major redesign, with change/relocation of gas porting, thus making the barrel free from piping at it's half length, in order for cannon to fit to the Bf 109. Source: 'Rapid Fire', book by Tony Williams, pg. 168
The MK 103M was to be installed on the Bf 109K-8, K-10 and K-14, but war ended that plan obviously. link
So your answer is a prototype cannon that never actually entered production by the end of the war? When is it supposed to be available for your tank busting Bf109 with HS12Y engine? Also wasn't your solution originally that the barrel stuck out beyond the propellor? So why would the length of the barrel matter?

Re. killing the Il-2: I'm not moving the goal post. This is what a Bf 109 with big cannon could've done, apart from killing tanks. Unlike what could the Stuka of Hs 123 or Hs 129.
Why would it be needed for that when that is the job of regular fighters and they did the job just fine? Why not just make more regular Me109s to Sturmovik kill?

The Fw 187 with same engines as Bf 110 will be a better performing A/C. In presence of Allied fighters the Bf 110 was not in favorable position.
Sure, but would be used as a fighter, it would be an even faster fighter-bomber, less well suited for tank busting given the high performance engine. The Bf110 was a solid, though slow ground attack aircraft when equipped with the proper gear, the Fw187 could have done the role, just less well. Plus it wouldn't have been able to night fight given the lack of German microwave radar gear.


Edit:
I'm not trying to be a dick here, but if you're proposing something like the HS12Y Bf109 with long 30mm MK you've got to demonstrate it was possible and viable.
 
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So your answer is a prototype cannon that never actually entered production by the end of the war? When is it supposed to be available for your tank busting Bf109 with HS12Y engine? Also wasn't your solution originally that the barrel stuck out beyond the propellor? So why would the length of the barrel matter?

No, my answer is a suitable engine where the cannon that is in production can fit, as I'm trying to explain you last two days.
It is not length of the barrel that matters for the installation of the big cannon in the DB or Jumo engine, but it is the gas port(s)' tubes that make total width of the cannon's mid section greater than it is a diameter of blast tube - like it was the case with MK 103. A modification that removes the ports and tubes is what brings the mid section of the cannon within the blats tube's diameter.


Why would it be needed for that when that is the job of regular fighters and they did the job just fine? Why not just make more regular Me109s to Sturmovik kill?

The regular Me 109s can't kill tanks, and tank's need killn'.

Sure, but would be used as a fighter, it would be an even faster fighter-bomber, less well suited for tank busting given the high performance engine. The Bf110 was a solid, though slow ground attack aircraft when equipped with the proper gear, the Fw187 could have done the role, just less well. Plus it wouldn't have been able to night fight given the lack of German microwave radar gear.

My intention is not to have Fw 187 as a night fighter, nor I remeber suggesting that. The Bf 110 does not mix well with Allied fighter either.
 
How about handwaving the US early mis-fires (pun intended) with 20mm guns and give the P-47 4x20mm's Hispano's? Or as long as I'm in full conductor mode on hand-waving problems away; the perpetual pre-war favorite 4x23mm Madsen's?

That's one thing I couldn't figure out, saying they were unreliable, when the European fighters that used the 20&23 of that family reported no such trouble, yet you can read plenty on all the faults the .50s had in early 1942, like the Doolittle Raiders had real issues with getting enough working .50s for the mission. There's a reason why some of those early US fighters kept the .30s, they were more reliable at first. But the cult of the Ma Deuce wrote most of the histories.....
 
That's one thing I couldn't figure out, saying they were unreliable, when the European fighters that used the 20&23 of that family reported no such trouble, yet you can read plenty on all the faults the .50s had in early 1942, like the Doolittle Raiders had real issues with getting enough working .50s for the mission. There's a reason why some of those early US fighters kept the .30s, they were more reliable at first. But the cult of the Ma Deuce wrote most of the histories.....
The problem wasn't the 20mm, the problem was the US version, AFAIK in converting Metric to US Customary they screwed up and took far too long to unscrew them
 
That's one thing I couldn't figure out, saying they were unreliable, when the European fighters that used the 20&23 of that family reported no such trouble

If you are referring to 20 and 23mm Madsens not giving any trouble, it's kinda hard to find a service record for their use. It was easy to find out that the first 10 Fokker D.XXIs license-built in Denmark didn't have their Madsens yet fitted when their war ended. Fokker G.I started with 2 Madsens, but stopped. Thailand use Madsens but I haven't heard a peep. It's quite true that there are no reports of trouble, but also, there are no reports of use.
 
If you are referring to 20 and 23mm Madsens not giving any trouble, it's kinda hard to find a service record for their use. It was easy to find out that the first 10 Fokker D.XXIs license-built in Denmark didn't have their Madsens yet fitted when their war ended. Fokker G.I started with 2 Madsens, but stopped. Thailand use Madsens but I haven't heard a peep. It's quite true that there are no reports of trouble, but also, there are no reports of use.

The 20mm was popular for a light anti tank gun and AAA. No fault with them in Finnish or German service
 
I do have this idea for a biplane, WW1-era "tank buster" aircraft for an ATL extended WW1 where one side uses tanks more often and the other side comes up with said aircraft to deal with them; sort of like an early 20th century expy of the A-10 Warthog.
 
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