He-111 as cargo aircraft.

[davebender]

The He-111H bomber performed well during the Stalingrad airlift.

2 tons. Average cargo carried per trip by Ju-52.
2.4 tons. Average cargo carried per trip by He-111H.

The He-111H also proved more capable in foul weather and was more survivable vs enemy fighter aircraft. The primary disadvantage was lack of a proper cargo deck and cargo hatch as they used bombers for the Stalingrad airlift.

Makes me wonder how capable the He-111H would have been if the Luftwaffe had purchased a variant designed specifically for air transport. Delete the bomb bay and bombardier nose. Install a proper cargo deck. Add a rear cargo ramp similiar to the Ju-252 and Ju-290.

 

[Shortround6]

You don't really need the rear ramp on a He-111. Just a good sized door in the side like a C-47. The Ramp is just going to suck up weight and fabrication time without really adding much to the ability. Does the He 111 really have the room inside for even a Kubalwagon? The rear fuselage tapers too much to get much use out of a ramp. See: http://109lair.hobbyvista.com/111/luft/v2_d-alix.jpg

 

[tyrodtom]

The wingspars of the He-111 went right through the fuselage full height. Early in it career when it was used as a airliner, the passengers had to climb over them. It would take a complete redesign to somehow reduce the height of those spars to make a usable cargo floor. The He-111 may have been able to lift the weight, but didn't have the room for bulky cargo that wasn't concentrated in weight. The long tail that appears to the roomy is just space that can't carry weight because it would put the CG out of bounds,

 

[Siegfried]

The He-111H bomber performed well during the Stalingrad airlift.

Makes me wonder how capable the He-111H would have been if the Luftwaffe had purchased a variant designed specifically for air transport. Delete the bomb bay and bombardier nose. Install a proper cargo deck. Add a rear cargo ramp similiar to the Ju-252 and Ju-290.

It should have been possible to retain the wing, undercarriage and empenage, control rigging and just redo the fueselage; something like a DC-2/DC-3 or shortened FW 200. The basic He 111 seems to have been suitable for certain kinds of cargo: dense things such as ammunition, possibly drums of fuel and high priority human caro. It's speed of course was of great use as was its range. Not only can such an aircraft avoid interception more easily it can do more trips per day. I'd say almost twice as many or from greater distances.

 

[davebender]

That pretty well answers my question.

Except as an emergency measure the He-111 was inheritly unsuitable as a cargo aircraft. If you are going to spend money on a new cargo aircraft it should be designed for that job as the Ju-252 and Ar-232 were.

 

[Siegfried]

The spar going through the floor is not a impossible problem for passenger aircraft: the Boeing 247 had this problem and the 20 seat Hawker Siddely Jetstream I travel on does as well.

He 111 was originally designed as a fast passenger aircraft and mailplane and then adapted as a bomber but it certainly emphasised speed over space. It's no suprise it did reasonably well as a transport in some niche areas. A Ju 88 or Handley Page Hampden certainly couldn't have done that job at all.

 

[davebender]

Perhaps not but it's far from ideal. Germany had plenty of better cargo aircraft designs to chose from so why produce the He-111H as a cargo aircraft?

 

[FLYBOYJ]

One pilot in a multi-engine aircraft is not a good risk mitigation configuration, although the Lancaster was configured that way.

 

[davebender]

Lancaster bombers had about a 5% chance to get shot down per mission over Germany. Under those circumstances it's best to keep the aircrew as small as possible.

 

[FLYBOYJ]

Lancaster bombers had about a 5% chance to get shot down per mission over Germany. Under those circumstances it's best to keep the aircrew as small as possible.

In the short term. Many Lancasters were also lost due to pilot error especially due to workload in bad weather and in the end that's why a two man crew became the norm for multi-engine aircraft

 

[Siegfried]

In the short term. Many Lancasters were also lost due to pilot error especially due to workload in bad weather and in the end that's why a two man crew became the norm for multi-engine aircraft

The Lancasters also weren't formation flying. The two pilots in a box formation would often call upon each other to assist in maintaining formation. No power controls in those days. I also suspect the Lancaster spent most of its time flying under autopilot. Night flying with only a single pilot member does sound hazardous.

 

[Siegfried]

Perhaps not but it's far from ideal. Germany had plenty of better cargo aircraft designs to chose from so why produce the He-111H as a cargo aircraft?

I suspect most of the He 111 transports weren't new builds but converted (and likely salavaged) bombers that had become obsolescent. The other answer is that they had all the tooling and jigs and experience to mass produce. Mass production seems to cut manhours to produce a completed airframe by a factor of 4 but I suspect the investment in time and money to produce those jigs is substantial. The Ju 52 hardly required any jigs. I'm not exactly an expert in the art of airframe construction but I think the jigs are very precisely made and thought out frames that allow the aluminium to be fitted and rivetted often with temporary clamps to get the shape and tollerances correct. They are often made in halves so that the frames came be joined after fitting out. The tooling would be (wooden) female dies onto which rubber (male) dies would be pressed to get the curved parts of the airframe correct. Without this the sheet would be beaten I think much of the DC3 was flat sheet but parts like the nose cone and the wing fueselage fillet was pressed. Tooling would also cover presses to cut out shapes such as wing cross sections, as opposed to nibbling it out. Ultimately there would be parts of the airframe made by forging or welding.

An old neighbour once gave me a book on DC3 maintenance and repair. Just about every part of the aircraft airframe could be made in an airline workshop.

 

[davebender]

Maybe that's why it was dirt cheap, costing about half as much as more modern aircraft such as the Fw-200, DC-3 and He-111. But you can do only so much with an airframe originally designed during 1930.

 

[FLYBOYJ]

The Lancasters also weren't formation flying. The two pilots in a box formation would often call upon each other to assist in maintaining formation. No power controls in those days. I also suspect the Lancaster spent most of its time flying under autopilot. Night flying with only a single pilot member does sound hazardous.

It is. and you're not flying flying formation on autopilot either

 

[FLYBOYJ]

I suspect most of the He 111 transports weren't new builds but converted (and likely salavaged) bombers that had become obsolescent. The other answer is that they had all the tooling and jigs and experience to mass produce. Mass production seems to cut manhours to produce a completed airframe by a factor of 4 but I suspect the investment in time and money to produce those jigs is substantial. The Ju 52 hardly required any jigs. I'm not exactly an expert in the art of airframe construction but I think the jigs are very precisely made and thought out frames that allow the aluminium to be fitted and rivetted often with temporary clamps to get the shape and tollerances correct. They are often made in halves so that the frames came be joined after fitting out. The tooling would be (wooden) female dies onto which rubber (male) dies would be pressed to get the curved parts of the airframe correct. Without this the sheet would be beaten I think much of the DC3 was flat sheet but parts like the nose cone and the wing fueselage fillet was pressed. Tooling would also cover presses to cut out shapes such as wing cross sections, as opposed to nibbling it out. Ultimately there would be parts of the airframe made by forging or welding.

An old neighbour once gave me a book on DC3 maintenance and repair. Just about every part of the aircraft airframe could be made in an airline workshop.

You are ust about correct on all points. "Production Tooling" or jigs are a science in themselves. For precision assemblies your tooling would be made from metal, usually steel. Wood would be used for more non-precision assembly or support cradles.

As far as the Ju 52 not having a lot of assembly jigs - I'd like to know your source and comparison to what as even the simplest aircraft that are mass produced are going to require some type of tooling, and I haven't even scratched the surface on smaller assembly tools and jigs for sub assemblies and detail parts.

Here is a P-38 center wing in the assembly jig. Same principal is still used today.