Sten SMG aircraft: productionized aircraft part 1, the reality

[BarnOwlLover]

This is about the simplest, but most effective, aircraft of World War II among both the Allies and the Axis. This is more about the aircraft that were produced that were at least fairly easy to produce or were designed with an eye toward production. I'm expecting already that this will feature discussion about the Mosquito, P-51, P-40, Hurricane, and Soviet aircraft. Also, this will involve aircraft that were also easy to maintain and repair as well. Focus, though, will be on those that made it into service.

 

[SaparotRob]

I'll take a stab. The P-36.

 

[tomo pauk]

Bf 109 was probably the epitome.

 

[GrauGeist]

Is this focused on fighters, or is any military aircraft qualified for the discussion?

If so, than I would say observation/trainer types like the dh.94, Bü181, PT-19 and KI-55 would be the easiest to build and maintain.

 

[GregP]

I'm thinking the simplest was the Vickers Venom. It did NOT make production, but was extremely simple and robust. Likely SHOULD have made it into production.

Straight, untapered wing, easy fabrication, lots of "easy to make and repair" type features. A low-wing monoplane single-seat, single-engined, eight-gun fighter aircraft. It was fast and manoeuvrable but its Bristol Aquila radial engine was underpowered. Together with other designs built to the same specification, which included the Bristol Type 146, Gloster F.5/34, and Martin-Baker MB 2, it was rejected by the Air Ministry and only one Venom was built.

Hard to imagine an easier-to-make, easier-to-repair aircraft.

So, naturally, they didn't build it!

 

[tomo pauk]

So, naturally, they didn't build it!

Kudos to the people in the British Air Ministry for that decision, and thank them 1000 times from the free world.

 

[Shortround6]

I'll take a stab. The P-36.

change the engine, it is a P-40.

 

[Shortround6]

Vickers Venom

Bristol sleeve valve Aquila engine.

Now take whatever pre WW II Hallucinogenic drug you prefer and figure out how to get the advertised performance out of engine that was 70% of the size of the engine in an AT-6.

Maybe they really did use a Jockey pilot (120lbs dressed instead of 200lbs)

The problem with most (all) of the light weight fighters is that the operational equipment (instruments, radios, pilot armor, etc) cannot be scaled down to suit the power of the engine.

Some the Venoms performance can also be credited to the Hamilton Standard Propeller, a rarity among British aircraft of time. However this also means there is no boost in performance when the Constant speed props show like the Hurricanes and Spitfires got.

 

[SaparotRob]

change the engine, it is a P-40.

I may have misread the OP. I thought we're going for simple. P-36. Radial. Less plumbing.

 

[GregP]

Kudos to the people in the British Air Ministry for that decision, and thank them 1000 times from the free world.

I can think of all kinds of places where some, cheap, easy-to-make and repair Venoms would have been a heck of a lot better than no air support. They had plenty of "no air support" around the world in WWII.

 

[Shortround6]

I may have misread the OP. I thought we're going for simple. P-36. Radial. Less plumbing.

but most effective,

A long nose P-40 was about 30mph faster than a P-36. we can argue about effectiveness.

The "simple" idea sounds good for about 3 seconds. Then reality kicks in. Much like the light weight/cheap fighter theory.
Lets break a few things down.
Landing gear, once you use retracting landing gear the parts numbers are not that much different. A larger fighter will use bigger, heavier parts but it doesn't use more of them, Like twin hydraulic struts for each wheel. So landing gear maintenance is roughly the same. Russians tried to use pneumatic retraction but they had more failures, including landing gear collapsing while parked. Brake maintenance?
Radios, unless you do away with the radios or try to use a single channel you have mostly the same maintenance issues aside form access (hatches) issues.
Instrument panels. Unless you leave out instruments (some I-16s didn't have fuel gauge, Pilot depended on his wrist watch and the sound of the engine) most planes are going to need pretty much the same maintenance.
Armament, again, unless you leave out guns (four .303s vs eight .303s) there is not a much savings there. OK Hurricane only had 3 doors to expose 4 guns vs the 4 doors on the Spitifre per wing but you have to pull all the guns out, break them down, clean them, reassemble and reinstall. total time saved by the better door arrangement??

engines? V-12 or 9 cylinder or 14 cylinder or 18 cylinder?
French tried a few planes with 700hp 14 cylinder radials, spark plug and valve adjustment were going to take pretty much the same time as a 900-1200h 14 cylinder radial. time it takes to open and close the cowl vs the time it takes to do the plug change and valve check/adjustment?

Some planes were designed for better access or fewer parts. But a lot of airframes were designed to go for several hundred hours without taking the basic airframe apart.
Repair battle or crash damage is a bit different than normal maintenance.

And if you sacrifice combat effectiveness for ease of maintenance/repair you may wind up doing a lot more repair

 

[Shortround6]

repair Venoms

with no armor, no self sealing tanks, only 56 Imp gallons of fuel, no bomb load. I am not sure how much support you actually get for what they cost you.

British tried Lysanders, Battles and Blenheims over France in 1940, didn't work very well.

If you try to make a 9 cylinder Taurus instead of the Aquila you get about a 740hp engine that weighs somewhat more than the Aquila, Next step is a Mercury which weighs about 200lbs more plus the bigger prop.

 

[GregP]

with no armor, no self sealing tanks, only 56 Imp gallons of fuel, no bomb load. I am not sure how much support you actually get for what they cost you.

British tried Lysanders, Battles and Blenheims over France in 1940, didn't work very well.

If you try to make a 9 cylinder Taurus instead of the Aquila you get about a 740hp engine that weighs somewhat more than the Aquila, Next step is a Mercury which weighs about 200lbs more plus the bigger prop.

It's tough to know when history only saw one that never made it into combat, Shortround6. I still think some support in areas that had none would have been better than what they had but, in the end, "what ifs" are sort of not my cup of tea.

I'll just say I think they wasted a decent opportunity for lower-priority areas that would not have used up any engines or many resources that were actually used for other aircraft other than the guns and ammo, neither of which they were short of at any time.

It had decent performance (315+ mph, 3000 fpm rate of climb) for the installed power. But, history sort of is what it is, and the Venom never made it into production and got consigned to the rubbish bin of prototypes that didn't make it. Meh.

Cheers.

 

[BarnOwlLover]

Basically here I'm asking about the best balance of capability vs ease of maintenance/production of those aircraft that did make it into production. This can include aircraft built in small series that may or may not have been confirmed to see combat, as well as those that were widely produced and used. We can obviously discuss both.

In the What If area, I did set up a somewhat similar thread that goes more into the "what if" as far as prototypes or small production aircraft

Example for here would be stuff like say the P-51, P-40, Hurricane, Mosquito, most Soviet fighters, as far as mass production. Small series that could apply here are possibly the Arsenal VG-30 series.

For the "what if", we can talk about things like the Venom, the VL prototypes/projects, the Miles M20, etc.

So far, I've mentioned mostly fighters, but recon and bomber aircraft also apply here, ie, combat/combat capable aircraft, but specially made suicide/kamikaze aircraft don't really apply here, though.

 

[GrauGeist]

So trainers/observation aircraft would then, most likely, be at the top of the list.

 

[GregP]

When you talk ease of maintenance, I'm assuming you mean the airframe. Any aircraft with a radial engine takes a certain amount of a certain type of maintenance, and an F6F Hellcat takes the same engine care as a P-61 Black Widow except the Black Widow has two of them. That said, any R-2800-powered airplane takes similar engine care.

Ditto inlines. Some require more maintenance than others, but all are similar. A Merlin takes more maintenance than an Allison, but the tasks are generally similar with the exception of the every 25-hour head torque requirement. You don't have to do that to an Allison. Not sure on DB601/5.

So, I am assuming airframe maintenance.

For general simplicity, the F4F and F6F are hard to beat. They are rugged and are not difficult to work on in any particular way. Also, unless damaged, they don't actually require a lot of work. Engine changes are relatively easy compared with something like a P-38. Actually, ANYTHING has an easy engine change compared with a P-38. But, the F6F is simple. rugged, and generally easy to maintain.

So, I'd nominate a land-based F6F Hellcat. That might change if operated from a carrier since carrier landings are basically controlled crashes and multiply maintenance requirements. Add the fact that the Hellcat was the top combat aircraft in the US arsenal in air-to-air combat and you have a winner.

 

[tomo pauk]

Straight, untapered wing, easy fabrication, lots of "easy to make and repair" type features. A low-wing monoplane single-seat, single-engined, eight-gun fighter aircraft. It was fast and manoeuvrable but its Bristol Aquila radial engine was underpowered.

Vickers Venom

Bristol sleeve valve Aquila engine.

Now take whatever pre WW II Hallucinogenic drug you prefer and figure out how to get the advertised performance out of engine that was 70% of the size of the engine in an AT-6.

Maybe they really did use a Jockey pilot (120lbs dressed instead of 200lbs)

The problem with most (all) of the light weight fighters is that the operational equipment (instruments, radios, pilot armor, etc) cannot be scaled down to suit the power of the engine.

People at Vickers used the oldest trick from the book - not installing any gun on the aircraft. Sure makes an aircraft going faster, be maneuverable, and climb better.

 

[GregP]

C'mon, Tomo, let's hear a good argument, not a one-liner.

 

[tomo pauk]

C'mon, Tomo, let's hear a good argument, not a one-liner.

Fair enough.

I'm thinking the simplest was the Vickers Venom. It did NOT make production, but was extremely simple and robust.

Simple - it probably was. Robust - according to whom?

Straight, untapered wing, easy fabrication, lots of "easy to make and repair" type features. A low-wing monoplane single-seat, single-engined, eight-gun fighter aircraft.

It have had no guns installed.

Hard to imagine an easier-to-make, easier-to-repair aircraft.

RAF (as well as other air forces/services of the time) were looking for aircraft that can bring required firepower to the piece of the sky, within time required, in order to kill enemy aircraft. Unarmed aircraft don't qualify, no matter how they are easy to repair or easy to make.

It had decent performance (315+ mph, 3000 fpm rate of climb) for the installed power. But, history sort of is what it is, and the Venom never made it into production and got consigned to the rubbish bin of prototypes that didn't make it. Meh.

No guns, no ammo. No flight test report, making the speed and RoC figures suspicious as the 400 mph XP-39, XF4U-1 and XP-38 turn of speed.
RAF/AM did the right thing when decided not to buy it.

 

[Shortround6]

It is another aircraft that has a lot of wishful thinking applied to it.
Nobody seems to have know what Bristol did to the engine to get near 600hp at altitude out of it. Assuming that they did get 600hp at altitude out of it.
We get things like this

Bristol Aquila AE-3S delivering approx 620 brake horsepower at 3,550 rpm at 13,500 ft with +5 lb boost.
Granted it used a bit shorter stoke than the Taurus but production Taurus engines were usually rated rated at 3100rpm at 3,000ft using 4.75lbs of boost. And they had trouble overheating.

Vickers Venom fighter

dingeraviation.net

has some interesting details including a forced landing by Geoffrey Quill when the engine stripped it's sleeve valve gears and also stripped the the main reduction gears disconnecting the prop from the engine. Anything can happen to a prototype engine.
However the alternative engines put forward while small, are huge compared to the Aquila. One suggestion is the P&W R-1535 bit that engine is close to 1100lbs and the Alvis engine (licensed G-R M 14) is around 925lbs but it is the same engine the French used in the some of their twins and was swiped for the HS 129 and didn't earn a good reputation anywhere.

It also claims this.
Weight: (Loaded) 4,185 lb (1,898 kg) including 50 gallons of fuel, ballast weight of 8 machine guns, 2,400 rounds of ammunition and TR9 radio.

Of course in true internet fashion the site goes on to speculate about putting in two 20mm guns and keeping four .303 guns and mounting drop tanks in a carrier version.
Also lists the wing as 170 sq ft while most other sources say 146sq ft. However trying to measure the cord on the wing on drawings seems to come closer to the 170 Sq ft number.
146 sq ft needs a wing cord of about just under 4.5 ft. ????