Improve That Design: How Aircraft Could Have Been Made Better

[tomo pauk]

...
The British didn't have a suitable HMG in the late 30s or 1940, perhaps they could have.
The .5in Vickers was large, heavy and suffered from jams even though it rarely actually broke. (How do you define reliability?) it also didn't have a particularly high rate of fire.
Provision of truly effective ammo was a problem, No HE rounds and good incendiaries only came later?
Of course the Germans didn't have a heavy machine gun either in 1939/40. They were working on one but it doesn't really see service until 1941.

There was several British (mostly Vickers-made) HMGs, reliable and all that jazz, that required just a will to adopt to RAF needs by 1930s. link
Of course, both British and Germans can buy licence from USA or Italy in mid-30s.

Both the Germans and the British advocates in these retrospective exercises have to be careful not to fall into the trap the US did historically. Over arming the planes for the engines that existed at the time.
The larger, heavier FW 190 airframe may not have worked very well with a 1940 DB 601 engine

Airframe (fuselage, wing, undercarriage, tail, controls & control surfaces) of the Fw 190V1 prototype weighted 760 kg (1765 lbs). Powerplant (engine, prop, cooling cotrols, oil system, cowling) represented around half of in-service Fw 190A's empty equipped weight - 1661 kg (3670 lbs).
Airframe of lightest P-40 ('no letter') went to 2200+ lbs.

Same with adding a cannon to early JU 87s. Even with an early Jumo 211 do you want to try sticking a cannon through the prop? and to what purpose?
An MG FF with a 55/60 round drum is certainly not a tank killer. Perhaps you could use that whacking big gun that used 20 X 138 ammo but it weighed 64kg without ammo.

Yes, I want that big whacking gun (roughly size of Hispano II), with 100 rd box, to kill some 'soft' targets - trucks, carriages, artillery. Ju 87 was no slouch in carrying ordnance, even with the earliest Jumo 211.

 

[Kevin J]

The Merlin XX had a higher gear for the supercharger in FS gear than the Merlin 45 had for its only gear. Thus it had a higher critical altitude than the 45.

A Merlin XX powered Spitfire would have been more competitive with the Bf 109F-4 and Fw 190A than the Spitfire V was.

The Spitfire was not deployed overseas initially because there weren't enough built that could be used for the home front and deployed overseas. In a shocking decision the Air Ministry/RAF decided to keep Spitfires defending British skies and deployed Hurricanes to what were considered secondary theatres.

The Merlin XX made the Hurricane more competitive, but that's not to say they were truly competitive in the ETO.

And, as I have said before, number of kills speaks more to opportunity than effectiveness.

Perhaps you can come up with some figures on Hurricane vs Spitfire victories in the UK after the BoB and up to the Dieppe raid. IIRC the Hurricane was still scoring well up to the introduction of the Spitfire Vb even Fw 190A. The Hurricanes supplied to the USSR were operating successfully during the first 5 months of 1942; admittedly no aces unless you include shared victories.

 

[tomo pauk]

For the 'Muricans:
- P-51 + V-1650-1, ASAP
- P-47 with proper drop tank facility, ASAP
- P-38 as a classic twin, with leading-edge radiators
- P-39 with 20mm + 2 HMGs, two drop tanks
- P-43 with V-1710

 

[gomwolf]

G.56 + DB603E + MW50 + Leading edge slat.

 

[Simon Thomas]

Short Stirling + 112' wing span - 9000+ lbs of "good ideas" from the air ministry - 3° incidence by undercarriage extension = rather good bomber

 

[tomo pauk]

Random bombers:
- B-26 with fuselage tailored around a bomb bay and crew of 5
- pre-Tu-2 with AM-38
- less ambitious Ju 288 with BMW 801, later with DB 603
- A-20 + turbo V-1710

 

[Shortround6]

There was several British (mostly Vickers-made) HMGs, reliable and all that jazz, that required just a will to adopt to RAF needs by 1930s. link

http://www.quarryhs.co.uk/Vickers.html

There was a bit of NIH in that report. The .5 Vickers was just a scaled up .303 Vickers with just about all the advantages and disadvantages. The manual for the .303 Vickers is supposed to list 26 or 27 different "stoppages", many of which can be diagnosed by noting the exact position of the cocking handle and some of which can be cleared with a good thump to the gun and tug or push on the cocking handle, some cannot but are still quickly cleared by a knowledgeable gunner. The Vickers had a very good reputation for durability and rare parts breakage. But it's "reliability" and rate of fire were why the RAF replaced it with the Browning for wing mounted guns. Going back to the Vickers for wing mounted guns may not have worked well.
The article you referenced uses the wrong ammo information for the .50 cal under test. The 710 grain bullet and 2900fps MV wouldn't exist until about 1940. The British wouldn't get such ammo until later.

Of course, both British and Germans can buy licence from USA or Italy in mid-30s.http://www.quarryhs.co.uk/Vickers.html

http://www.quarryhs.co.uk/Vickers.html
In the Mid 30s the US still had the low velocity ammo. The M2 gun with it's improvements might be available instead of the M1924 gun though.

Airframe (fuselage, wing, undercarriage, tail, controls & control surfaces) of the Fw 190V1 prototype weighted 760 kg (1765 lbs). Powerplant (engine, prop, cooling cotrols, oil system, cowling) represented around half of in-service Fw 190A's empty equipped weight - 1661 kg (3670 lbs).
Airframe of lightest P-40 ('no letter') went to 2200+ lbs.

We seem to have a disconnect here. The Fw 190V1 Prototype according to one source (which could be wrong) used a 160sq ft wing and the BMW 139 engine that was 350lbs lighter than the BMW801 ? according to this source the entire structure had to be stressed and strengthened. Normal loaded weight without armament had grown 25% to 7,550lbs (?) and wing loading had grown to 46.6lbs/sq/ft. A new wing of 196.98 sq ft was designed.

Yes, I want that big whacking gun (roughly size of Hispano II), with 100 rd box, to kill some 'soft' targets - trucks, carriages, artillery. Ju 87 was no slouch in carrying ordnance, even with the earliest Jumo 211.

The gun only has a limited application. the rate of fire is 300-350rpm or 5-6 rounds per second. The ammunition is somewhat more powerful than the Hispano, but if you are using HE ammo the impact velocity is a lot less important. There was an AP round but once tanks went beyond 14-15 mm armor it's utility dropped considerably. For soft targets you might be better served by an extra MG 17 in each wing, or two. At up to 20 rounds per second per barrel against soft targets the likelihood of getting multiple hits goes way up. An extra pair of MG 17s might see around 8 hits (on top of the hits from the existing wing guns) for every 20mm hit.

 

[wuzak]

Perhaps you could use that whacking big gun that used 20 X 138 ammo but it weighed 64kg without ammo.

Is the "whacking big gun" the MG C/30L?

 

[Shortround6]

yes, Trying to use an MG FF through the prop of a JU 87 doesn't get you much as armor penetration is pretty crappy.

The MG C/30L is supposed to have knocked out a few tanks in Spain (3 Russian T-26 tanks?) which had 15mm armor pretty much all around on the vertical surfaces.

 

[sdmodeller]

Ok how about this one: P-39 with a merlin? Keep it a low level fighter but up the HP. Trash the 37mm and 30 cal. Basically 109F armament. She might a real minx then.

 

[wuzak]

Ok how about this one: P-39 with a merlin? Keep it a low level fighter but up the HP. Trash the 37mm and 30 cal. Basically 109F armament. She might a real minx then.

Which Merlin?

 

[PAT303]

The Merlin 45 was a derivative of the Merlin XX. It had the high altitude but not the low altitude performance. So what's wrong with what was done? Putting the Merlin XX into the Hurricane kept it competitive at all altitudes. It was a rugged fighter that could be deployed across the globe. Its aerial victory statistics back the decision up. The Spitfire was less rugged, scored fewer kills, and was not really deployable on the global scale until the Vc version.

The MkIII was redesigned using all the lessons learnt from the BOB, as Wuzak posted, the MkIII if built would have been the stand out fighter from 1940 onwards, it would also mean the MkVIII would be the main version instead of the interim Mk IX, in doing so fixing the single biggest downside to the spit, lack of internal fuel.

 

[Kevin J]

The MkIII was redesigned using all the lessons learnt from the BOB, as Wuzak posted, the MkIII if built would have been the stand out fighter from 1940 onwards, it would also mean the MkVIII would be the main version instead of the interim Mk IX, in doing so fixing the single biggest downside to the spit, lack of internal fuel.

The problem with that in the 1940/41 time period is the maxim 'no changes on the production line' as until the USSR was invaded there was still the danger that the Nazi's will invade. That's why only incremental changes were made to the Spitfire. The Spitfire Va/b aka Ia/b with the Merlin 45/46. I'm not doubting that the Spitfire III was excellent but when would it have entered service. As things were, the first production Vb's didn't arrive until June 1941 although Va's converted by Rolls-Royce from Ia's had begun arriving 3 months earlier. The Spitfire Vc didn't enter service until March / April 1942 and that had only a limited number of the changes from the Spitfire III.

 

[Ivan1GFP]

B-26 Marauder
*Go with the longer wing right from the start.
Fowler flaps.
*Redesign the bomb bay doors to eliminate drag. (Folding doors caused massive drag when open, reducing top speed by 25 mph.) Roll up doors like on B-24 were suggested, but never implemented.
Redesign bomb bay with capacity for tandem racks, thus eliminating need for second bomb bay. I was shocked at how much space was wasted when carrying smaller bombs.
*Move turret forward to improve CG.
Add RADAR.

*indicates a proposal that was not implemented

Hello Greg Boeser,
I believe one of the biggest design flaws of the Marauder was the choice of airfoil.
For a non-aerobatic aircraft, there really wasn't a good reason to use a symmetrical airfoil.
The lack of lift at low AoA eventually resulted in rotating the entire wing along with engines (B-26G) to increase incidence and lift at lower speeds but reduced maximum speed.
With a better high lift airfoil, they would not have had those issues to begin with.

I believe also that the rear bomb bay was simply not a good idea.

Ditching the Curtiss Electric propellers in favour of hydromatics might have resulted in fewer aeroplanes in Tampa Bay and fewer take off accidents. The design wasn't necessary a bad one, but gave too many opportunities for ground crew to screw up in handling APU and battery which resulted in not enough power for the propellers to work correctly.

AIrplanes have two CG or perhaps weight distribution problems is a better way of saying it. The first is flying and most of us are familiar with that. The second is landing and/or ground handling. Once a number of planes were modified with extra armament or operational equipment they managed to keep the flying CG pretty much in place but the ever increasing loads often strained the landing gear or made ground handling difficult. Pilots manual for even the B-25C/D prohibits pivot turns, notes that on soft surfaces the nose wheel can dig in a reverse itself (turn 180 degrees) if the tire sinks more than 2 inches into the soil. It suggests having a crew man walk in front of the plane monitoring the wheel if the ground is soft.

On some planes it was a trade off between more effective armament (or more effective placement) and increase ground accidents/ even if repairable.

On the B-26 they added tons of equipment/consumables to the original design. Moving the turret forward (to behind the pilots? ) would seem doable, but they were adding a single fixed .50 in the nose and the four cheek guns, Perhaps they needed the turret to stay where it was?
Of course they added more/bigger lower waist guns and an extra crewman? so perhaps moving the turret would help with that? B-26 went through a lot of weight shifts.

Hello Shortround6,
I believe the problem with the Marauder was that the CoG changed too much as equipment was shifted about or removed.
I am sure we have all heard about the case of nose gear collapses due to incorrect CoG resulting from misleading of equipment on the aircraft. The problem there seemed to be CoG too far forward rather than too far aft.

- Ivan.

 

[Ivan1GFP]

I believe the Mitsubishi A6M Type 0 would have done quite a bit better if the initial design had gone with the Mitsubishi Kinsei engine instead of the Nakajima Sakae. It may not have had quite the same range and agility, but would have stayed as a viable fighter for much longer.
The Japanese eventually came to the same conclusion when they fitted the Kinsei to the A6M8 but it might have been a whole lot better if it had been done 5 years earlier.

I also believe that the FW 190 series should have gotten an increase in the size of its wing. In the prototype stage, it had already gone from a 160 ft^2 wing to 197 ft^2 wing but weight increased substantially with production models and the size of the wing did not change. It also meant that if not properly flown, it had a tendency to mush. A wing with increased span may have improved the issue and as seen with the Ta 152 series, it did not drastically affect the roll rate.

Thoughts?
- Ivan.

 

[buffnut453]

In the Mid 30s the US still had the low velocity ammo. The M2 gun with it's improvements might be available instead of the M1924 gun though.

And the 50 cal in wing-mounted installations wasn't working...at least not reliably. Now, I'm sure it could have been fixed sooner that the latter half of 1942, as was the case in reality. Maybe that's an area where multiple US fighters could have been improved faster than the actual timeline?

 

[ClayO]

I agree with the idea. I'm curious why the British were so obsessed with the idea.

On the P61's turret: since the British wanted the P61 as a defense against buzz bombs, I've wondered if they wanted a way to shoot them down from some other position than directly behind - which forced the pilot to hit a difficult target from maximum range, then immediately veer away from the explosion on the first hit. It would still be difficult shot, but if the turret had worked, the interceptor could have behind or below the buzz bomb, and so could have been somewhat closer. As it was, the buzz bomb threat was pretty much over with by the time they fixed the turbulence problems caused by turning the turret in flight, so I don't know if there's any data on that.

 

[swampyankee]

On the P61's turret: since the British wanted the P61 as a defense against buzz bombs, I've wondered if they wanted a way to shoot them down from some other position than directly behind - which forced the pilot to hit a difficult target from maximum range, then immediately veer away from the explosion on the first hit. It would still be difficult shot, but if the turret had worked, the interceptor could have behind or below the buzz bomb, and so could have been somewhat closer. As it was, the buzz bomb threat was pretty much over with by the time they fixed the turbulence problems caused by turning the turret in flight, so I don't know if there's any data on that.

Adding the turret, gunner, and associated equipment probably made the performance needed to intercept the V-1 nearly impossible.

 

[Shortround6]

The Turret was incorporated almost from the start of design in 1941, well before anybody even knew what a buzz bomb was.

However, in 1940/41 airborne radar was not all it could be and had a minimum range of hundreds of yards which meant the final close to the target was often a visual search, target could appear enough off axis of the aircraft to prevent getting a firing pass, in which case it was hoped the turret could engage the target.
Preliminary design work started on the P-61 in the fall of 1940 and contract for two prototypes was signed Jan 30th 1941.
Please not that this perhaps limits both the engine selection and the configuration of the fuselage as Jack Northrop is not really given any details at all on "Radar". He is merely told that
[that there was a way to "see and distinguish other airplanes" ]

so minor details (sarcasm) like volume and weight of this device (or if it needs extra crewmen) are not available early in the design.
Over 400 were on order several months before the first XP-61 makes it's first flight on May 26th 1942 (no, you can't make them available for Midway

" thirteen YP-61s were delivered during August and September of 1943 "
"The YP-61s initially did not have any airborne interception radar fitted, but the SCR-520, a preproduction version of the SCR-720 which was to go into the production P-61A, was installed"

Quotes from Joe Baugher's web site.

Proposals for skinny fuselage P-61s with all fixed guns from the start should tale these factors into account.

 

[tomo pauk]

Untitled Document

There was a bit of NIH in that report. The .5 Vickers was just a scaled up .303 Vickers with just about all the advantages and disadvantages. The manual for the .303 Vickers is supposed to list 26 or 27 different "stoppages", many of which can be diagnosed by noting the exact position of the cocking handle and some of which can be cleared with a good thump to the gun and tug or push on the cocking handle, some cannot but are still quickly cleared by a knowledgeable gunner. The Vickers had a very good reputation for durability and rare parts breakage. But it's "reliability" and rate of fire were why the RAF replaced it with the Browning for wing mounted guns. Going back to the Vickers for wing mounted guns may not have worked well.
The article you referenced uses the wrong ammo information for the .50 cal under test. The 710 grain bullet and 2900fps MV wouldn't exist until about 1940. The British wouldn't get such ammo until later.

I will not claim here that Vickers (H)MGs were the next best thing after sliced bread, however there was more than a decade worth of time for the British to perfect both the HMGs and their installations before the war starts.

We seem to have a disconnect here. The Fw 190V1 Prototype according to one source (which could be wrong) used a 160sq ft wing and the BMW 139 engine that was 350lbs lighter than the BMW801 ? according to this source the entire structure had to be stressed and strengthened. Normal loaded weight without armament had grown 25% to 7,550lbs (?) and wing loading had grown to 46.6lbs/sq/ft. A new wing of 196.98 sq ft was designed.

This is partly the point why I've suggested a DB engine to be installed - originally, the heavy BMW 139 (850 kg 'naked') was supplanted by an even heavier 801 (935 naked, 1155 kg outfitted), indeed necessitating strengthening of airframe, as well as a new, bigger & heavier wing (18.3 sq m instead of 14.9). The DB 601A was at 610 kg 'naked' (720 kg outfitted); add ~150 kg worth of cooling system and we're at 760 kg - 90 kg less than BMW 139. No fancy and heavy oil system, a lighter prop.
The DB 601E went to 660 kg 'naked' (725 outfitted), that will be ~810 with cooling system, or almost 80 kg lighter than a naked 801C or D. No armored oil system either, a lighter prop. Engines' weights, ready to be installed, are 1155 kg for the BMW 801C/D vs. ~875 for the DB 601E.
Other reasons for the DB engine is actual availability, lower drag, a far better reliability and lower consumption.

The Fw 190V1 went to 3000 kg ready for take off, the armed V2 to 3150 kg.

The MkIII was redesigned using all the lessons learnt from the BOB, as Wuzak posted, the MkIII if built would have been the stand out fighter from 1940 onwards, it would also mean the MkVIII would be the main version instead of the interim Mk IX, in doing so fixing the single biggest downside to the spit, lack of internal fuel.

Spitfire Mk.III was not a whole redesign, but more of an ironed-out standard Spitfire - old wing, old fuselage, old tail, with aerodynamical nip & tuck there and there.