Transport aircraft layout

[kool kitty89]

Payload is important and here with early transports (low powered) we run into the volume problem, People are high volume/low weight "cargo". If you want to carry a lot of people you need a fat fuselage and that ups the frontal area and drag. If you want to carry heavy cargo you need a stronger floor than the a plane carrying people needs. If you want ramps for vehicles you need a heavier structure than a people carrier. You want landing gear that will handle rougher landing strips than a C-47 it will cost weight. You want short landing and take-off? it means big wing or high lift devices which cost weight and drag.

Ramps used on aircraft otherwise similar to transports limited to light and medium duty freight materials (and passengers) could still benefit from large loading ramps in terms of sheer loading/unloading time. The likes of the C-47 were already capable of carrying some light vehicles (at least up to the size of jeeps) but suffered more from loading/unloading times.

Lack of a wide body cabin is the main issue leaving the He 111 as a mediocre general purpose transport and the same factor that makes the cancellation of the Fw 206 curious. (appearing to use a fairly wide-bodied design akin to the FW 200, but somewhat shorter and built around two engines with roughly 59% of the total take-off power -comparing 2x Bramo 323R to 4x BMW 132Dc engines) From the limited information I can find on it, the Fw 206 seems fairly heavily based on the Fw 200 as well as similar in size and passenger capacity to the DC-3. (a shame development didn't start a bit sooner or run in parallel with the Fw 200 itself, but either way odd that it was canceled)

I don't have enough numbers to know if using GP (General Purpose) transports to tow assault gliders for tactical use is better overall than using assault transports year round as GP transports or not. A lot may depend on the percentage of varius types of missions done over a given time period.

You also have conversions of gliders to powered aircraft like the Me 323 and (perhaps more relevant) Go 244. If its range had been a bit longer, the Go 244 seems like it'd have been quite useful transport in its own right (perhaps even a total replacement for the Ju 52) and the construction materials and methods used for it certainly make it attractive. (something similar but slightly larger using 1000~1200 HP class engines -like 14Ns or Bramo 323s and considerably more fuel capacity would have been really interesting, somewhat like a miniature counterpart to the Ar 232)

 

[Koopernic]

Planes lost by the Luftwaffe during the Stalingrad air-lift.
During the Stalingrad air-lift (Nov. 24th, 1942 until Jan. 31st, 1943) (69 days)
the Luftwaffe lost 488 planes : an average of 7.07 transport planes a day.

266 Junker 52 (a third of Luftwaffe's total complement) (3.85 Ju52 each day)
165 Heinkel 111 (2.42 He 111 each day)
42 Junker 86
9 FW 200
5 Heinkel 177

166 planes were completely destroyed
108 planes were (are) missed (also the crews)
214 planes were lost during the take-off or landing
and written off

The total losses are the equivalent of five wings, or more than
one complete air corps.

About 1100 airmen died, (an average of 16 each day) including many
of the Lufwaffe's most experienced bomber and transport pilots,
navigators and training instructors.

Looking at those statistics tells us that Around 50% of losses were take-off and landing related, almost certainly in the Pocket itself rather than the surrounding supply airfields.

My conclusion is that an aircraft with excellent STOL performance would be required and that this feature transcends all others in importance if you are serious about tactical air supply.

The Luftwaffe almost had such an aircraft in the Arado 232B. It had a rear loading ramp, a 2m x 2.2m x 6m cargo area, a tricycle landing gear that could be supplemented by 22 smaller wheels that allowed taxing and takeoff/landing in sodden ground, it could take-off with 4tons of fuel cargo (say 2 tons cargo and 2 tons fuel) with only a 200m/660ft run. It didn't have a spectacular range, though might have been extended with drop tanks, it was still better than the Ju 52.

During the Stalingrad airlift the He 111 performed well compared to the Ju 52, carrying slightly more than the 2 tons a Ju 52 carried in on a good day. Its water cooled engine was also more robust in the cold, with the Ju 52 radial sometimes failing to start in extreme cold (on one day Ju 52 missions were completely scrubbed due to cold). It could carry up to 16 troops, it could carry two SB1000 parachute containers (up to 800kg payload but generally less than half that) which were a very important form of supply and I suspect the lack of cabin space for cargo hardly mattered when carrying dense cargos such as ammunition but would be frustrating if artillery or a small vehicle was required. (The German "kettenrad", half track motorcycle, could be airlifted by a Ju 52 and was used for towing. Obviously it couldn't fit in a He 111)

In the mess that was Stalingrad I feel the Ar 232B, if it had of been available in the same numbers as the Ju 52, might have made the difference. Not so much due to its heavier cargo but its ability to handle very rough fields, maybe it would have suffered no takeoff and landing losses since its strip length was about half that of the C-47 and Ju 52/3m. This would have opened up more of the 5 small airfields available.

Of course having a ramp would help enormously when needing to carry a howitzer, AT gun, AAA battery and a tractor to tow it as would being able to move in earth moving equipment such a small bulldozers ( 2.5-3 tons ) to improve the airfield and defences. You can even fly in steel plate mesh landing strip.

Another factor might be capabilities such as blind landing equipment that can do a STOL at night.

The other thing to note is that they were sometimes getting in only 80 aircraft in a day. Assuming a winters daylight is 8 hours (maybe less) that would be one every 6 minutes. One would need to get one aircraft in every minute to get enough supplies in.

 

[kool kitty89]

During the Stalingrad airlift the He 111 performed well compared to the Ju 52, carrying slightly more than the 2 tons a Ju 52 carried in on a good day. Its water cooled engine was also more robust in the cold, with the Ju 52 radial sometimes failing to start in extreme cold (on one day Ju 52 missions were completely scrubbed due to cold). It could carry up to 16 troops, it could carry two SB1000 parachute containers (up to 800kg payload but generally less than half that) which were a very important form of supply and I suspect the lack of cabin space for cargo hardly mattered when carrying dense cargos such as ammunition but would be frustrating if artillery or a small vehicle was required.

16 troops is a fair bit more reasonable than the 10 passengers the civilian models carried, though it's still no C-47.

And I wonder if it was more the fuel injection that mattered more in extreme cold than air vs water cooling. (that would be one of the advantages of the Bramo 323 over the BMW 132 as well, though apparently some military models of the 132 were fuel injected -and more competitive with the 323's power ratings- but I'm not sure of the usage of those types and they wouldn't be the engines used on those JU-52s either)

The Go-244 would be fairly useful for the specialized bulky airlift cargo, wouldn't it? (At least for the short-range tactical supply runs it was capable of)

 

[Shortround6]

Part of it may have been that it was easier to start 2 engines than 3. I am not sure how many engine heaters each squadron had and in Russia in the winter it was common to use two heaters on one engine.

Please remember there was NO multi-grade oil and there were 3/4 methods of dealing with cold weather starting as even if you had enough starter power to turn the engine over the thick oil sometimes broke the oil pump drive.
1. Drain oil after last flight and bring indoors where it could be kept warm or heated up in the morning before pouring back into aircraft.
2. Diluting the oil with gasoline during the last few minutes of running before shutting down. you need the diluted oil in the engine, not the tank when trying to start. the Gasoline evaporates out as the engine warms up while idling with no load.
3. Use forced hot air heaters with ducts and shrouds to warm up the engines before trying to turn them over.
4. Depending on circumstances more than one method would be combined.

It was also not unknown for things like the shock absorbers in the landing gear to freeze up (become immovable) leading to a new meaning for "fixed landing gear" especially on rough runways.

The air-cooled engines don't have a thermal "sink" which means they have to managed more carefully in cold conditions. P-47s could damage their engines by a too rapid decent at low power levels. It would bring the engine temperature below the minimum needed for good lubrication. I would guess that a number of other air cooled engines could suffer from the same thing.

JU-52 cowls do not have adjustable cowl flaps to help regulate air flow. Cowls aren't even the same on the fuselage engine and wing engines so they may not quite cool (or over cool) the same.

 

[Koopernic]

16 troops is a fair bit more reasonable than the 10 passengers the civilian models carried, though it's still no C-47.

The Go-244 would be fairly useful for the specialized bulky airlift cargo, wouldn't it? (At least for the short-range tactical supply runs it was capable of)

The Gotha Go 244 was of course developed from the Go 242 Assault Glider. The aircraft could carry a small car, typically a "Kubbelwaggon" the VW beatle based car, so it was quite useful. These were usually only a 2 wheel drive (the Germans couldn't afford to make too many of the 4WD versions) but because of the weight was over the driven wheels and because of a good limited slip differential and ground clearance it did well. This or a half track motorcycle could thus help move around an sizable artillery piece. The Germans had 75mm recoilless guns and shaped charge warheads for them but more ordinary guns and FLAK could it seems be moved around.

Unfortunately the Go 244 was found to be vulnerable to ground and air fire and losses were high. This is presumably due to its glider roots and insuffient protection in the form of armour and self sealing in the fuel tanks. Range is often given as 272 miles at seal level and sometimes 373 or even 470 (presumably at high altitude) so its radius of action was poor.

A characteristic of German transports is that they needed armament and were faced with frequent battle damage.

The Ar 232B was to have a 13.2mm heavy machine gun in the nose, a 20mm power drive dorsal turret and a heavy machine gun in the loading ramp that was fired by the load master. On each side there were 8 ports for paratroppers to fire their machine guns and rifles at an attacking aircraft. The German paratroopers FG 42 (German: Fallschirmjägergewehr 42) was probably the best weapon in the world at this time and offered full auto from a 20 round clip. This tactic had been found effective over the Mediterranean when A-20's had attacked Ju 52.

The Ju 352 did enter production, it had approximately the performance of the C-47 (not the stunning performance of the Ju 252) but it did have the loading ramp. The He 111 and Ju 352 would seem a reasonable combination. Only 45 were made with production stopping in September 1945 in favour of fighters.

Shortround6, I think the cowls were refered to as Townsend Rings.

 

[Shortround6]

Shortround6, I think the cowls were refered to as Townsend Rings.

The center/fuselage cowl definitely is. Some Ju-52s may have used them on the outer engines too but the one in the picture has different cowls. How deep/long you have go to change from a Townsend Ring to a NACA cowl I don't know but there were plenty of NACA cowlings in the 1930s without cooling flaps.

And we are back to what kind of transports the Germans needed/wanted. Defensive gun mounts suck up weight and add drag but help when in contested airspace. Do the Germans need assault transports or general purpose transports or both?


BTW a Kubbel waggon is about 3/4 of the weight of an American jeep so special loading/unloading arrangements, while nice, may not have been as necessary.

 

[GrauGeist]

...The aircraft could carry a small car, typically a "Kubbelwaggon" the VW beatle based car, so it was quite useful. These were usually only a 2 wheel drive (the Germans couldn't afford to make too many of the 4WD versions) but because of the weight was over the driven wheels and because of a good limited slip differential and ground clearance it did well.

From personal experience, I found that the VW bug had extremely impressive mobility in adverse driving conditions, such as deep snow, being only two wheel drive. I had a 1966 bug (1300 Type I engine) and in deep snow, where the bug was literally "sledding" along on it's belly pan, the rear wheels were digging down and gaining traction nicely due to the transaxle's swing-arm suspension. And the front wheels, while being suspended by the beam-axle, didn't really touch the ground but rather acted like rudders.

The Kubelwagon and the "bug" types used the same pan and suspension and were very nimble in all types of road conditions. There were limitations of course (like speed + cornering = big trouble in a Bug...lol)

 

[Koopernic]

From personal experience, I found that the VW bug had extremely impressive mobility in adverse driving conditions, such as deep snow, being only two wheel drive. I had a 1966 bug (1300 Type I engine) and in deep snow, where the bug was literally "sledding" along on it's belly pan, the rear wheels were digging down and gaining traction nicely due to the transaxle's swing-arm suspension. And the front wheels, while being suspended by the beam-axle, didn't really touch the ground but rather acted like rudders.

The Kubelwagon and the "bug" types used the same pan and suspension and were very nimble in all types of road conditions. There were limitations of course (like speed + cornering = big trouble in a Bug...lol)

The VW Kombi had a similar reputation for vans, could get you to the interesting surf spots. If a VW couldn't do it you shouldn't be wrecking the roads further.
Due to Wifey's insistence, she inherits the car next year and likes driving fast in the wet, I am in a Subaru XV Crosstrek, so I am in a car by the same people that gave us Nakajima. The Jeep was quite compact and could be air dropped from a Halifax. Both sides used parachute containers which could be released from standard bomb racks. Both sides used multiple parachutes. The half track motor cycle looks like a gimmick but it was of real use: it could carry two passengers, carry ammunition, tow artillery or bogged vehicles, lay communication cable and get through difficult quagmire and snow. Furthermore it fitted into a Ju 52.

Halifx dropping Jeep, British Paratroopers with mini bikes dropped in parachute containers. Not sure what happened to the 'silk'. I imagine the troops were quick to hide them.

Above a German PAK 36 37mm anti tank gun being dropped into Crete, Kettenrad could fit into a Ju52.

 

[kool kitty89]

Unfortunately the Go 244 was found to be vulnerable to ground and air fire and losses were high. This is presumably due to its glider roots and insuffient protection in the form of armour and self sealing in the fuel tanks. Range is often given as 272 miles at seal level and sometimes 373 or even 470 (presumably at high altitude) so its radius of action was poor.

A characteristic of German transports is that they needed armament and were faced with frequent battle damage.

A purpose-built transport aircraft of similar design and construction to the 242/244, but better equipped, more powerful engines (maybe 14k or Bramo 323) and longer ranged.

Ground fire vulnerability of the Go 244 was partially due to flying low and slow, but given the Ju 52 was no better there, the added vulnerability to ground fire would probably be limited to the lighter structure and lesser protection. (though the smaller size and target area would make it tougher to hit than a Ju 52)

Defensive armament aside, higher fuel capacity in self sealing tanks, and added armor would be necessary to properly militarize it.

The Ar 232B was to have a 13.2mm heavy machine gun in the nose, a 20mm power drive dorsal turret and a heavy machine gun in the loading ramp that was fired by the load master. On each side there were 8 ports for paratroppers to fire their machine guns and rifles at an attacking aircraft. The German paratroopers FG 42 (German: Fallschirmjägergewehr 42) was probably the best weapon in the world at this time and offered full auto from a 20 round clip. This tactic had been found effective over the Mediterranean when A-20's had attacked Ju 52.

The Ju 352 did enter production, it had approximately the performance of the C-47 (not the stunning performance of the Ju 252) but it did have the loading ramp. The He 111 and Ju 352 would seem a reasonable combination. Only 45 were made with production stopping in September 1945 in favour of fighters.

Higher priority certainly should have been given to the likes of the Ar 232 and Ju 252. My comments on the Go 244 were more in regards to smaller supplemental aircraft with rather useful configurations (and basic potential for being applied to larger/more capable counterparts).

As far as glider conversions went, the Go 244 and Me 323 were both rather interesting and novel designs, but not the most practical transport aircraft. Neither worked well in combat zones though ... and the Me 323 was massive and costly (if capable of doing things no other aircraft could). The Go 244 was probably much closer to managing being a much more useful general purpose transport. (the Ju 252 and Ar 232 would obviously be the more useful/substantial transports around)

BTW a Kubbel waggon is about 3/4 of the weight of an American jeep so special loading/unloading arrangements, while nice, may not have been as necessary.

Loading/unloading time is still a factor even when weight capacity is no better.

That said, a Kubbel waggon would be easier to get on and off a C-47 than a jeep, and if something along the lines of the Fw 206 could have managed similar, the advantages of something like the Go 244 would be more limited. (a more substantial aircraft similar to the 244 might have had other advantages)

 

[GrauGeist]

...The half track motor cycle looks like a gimmick but it was of real use: it could carry two passengers, carry ammunition, tow artillery or bogged vehicles, lay communication cable and get through difficult quagmire and snow. Furthermore it fitted into a Ju 52.
View attachment 288717

The Kettenkrad (SdKfz2) was also used to move aircraft, particularly the Me262.

(I wouldn't mind owning one, either!)

 

[Airframes]

Good stuff. A mate of mine had one of the para motor bikes years ago, back in the late 1960's/early 70's. Worth a small fortune now.
BTW, the parachute canopies were left on the DZ, the priority being to clear the DZ and re-group into respective units asap. With silk canopies, which were already starting to be replaced by the new Du Pont 'Nylon' material, they were gathered-up by the locals, to make dresses and underwear. Also, German troops in Normandy and Holland used strips cut from the olive green or khaki canopies as neck scarfs/sweat scarfs and dust protection for face and mouth.