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I have been looking at a lot of drawings and pictures of these vehicles, and to my untrained eye, it appears that this suspension was simpler in design than the inter-leaved road-wheels on production Tigers. Is this in fact the truth, or was there faults in the design that were not visually apparent?

remember the Elefant was based on the Porche Tiger Chassis not the Henshel one which actually won the competition and became the Standard Tiger tank. ( I think I got that right)

I wouldn't say a simpler suspension, different is probably a better word (did Porsche ever make something simple?). 6 boogies connected to longitudinal torsion bars. I need to fill in some blanks on this myself before I can give a more exhaustive answer.

- Tanklord

I have been looking at a lot of drawings and pictures of these vehicles, and to my untrained eye, it appears that this suspension was simpler in design than the inter-leaved road-wheels on production Tigers. Is this in fact the truth, or was there faults in the design that were not visually apparent?

Explain simple....

In terms of suspension, I'm not sure it was particularily simple. In a normal torsionbar suspension, you have a swingarm connected directly to a torsionbar running the width of the hull, so that movement of the wheel, acts on the swingarm which twists the torsionbar. Pretty straight forward.
As I understand the Porsche suspension, you got a fixed arm mounted on the hull, holding another arm which holds the two-wheel assembly where the wheels are mounted on a cylinder with a short, longitudinal torsion bar. When the wheels move, they act on the torsionbar by means of cams, acting on a ball which in effect turns the motion 90 degrees to work on the torsionbar. There seems to be a more independently moving parts, acting together in turning the forces involved and the short torsionbar allowed less movement of the wheel and resulted in a harder suspension, IIRC.

The Porsche suspension obviously had fewer roadwheels, which would be considered less complicated. However, the many roadwheels on the interleaved suspension distributed the weight of the vehicle much more evenly along the track, resulting in a much better cross country performance. Even though nominal ground pressure (NGP) would be the same for two similar vehicles regardless of the suspension type, the mean maximum (ground)pressure (MMP), which does a better job of describing how tanks actually perform, was a lot less with the interleaved suspension.

Where the Porsche suspension might have been simpler would be in hull manufacture, as the "normal" torsionbar suspension required some precision drilling of holes in the side armour, while the Porsche unit was bolted on, requiring a lot less work (140 hours vs 360 hours of work). The Porsche suspension was also lighter by about 2.7 tons and required less rawmateriels. This was the reason why the Porsche suspension was tried out on the Jagdtiger.

It's always been my understanding that, while the interleaved wheel suspension used on the Tiger and Panther made for better weight distribution and perhaps a smoother ride, they had the potential to create operational problems. Mud or snow/ice packed between the wheels led to immobilized vehicles. I read somewhere about panzertruppen using grenades during the Russian winters to "free up" their vehicles' suspensions after they had been parked overnight.

- A2_Prius

It's always been my understanding that, while the interleaved wheel suspension used on the Tiger and Panther made for better weight distribution and perhaps a smoother ride, they had the potential to create operational problems. Mud or snow/ice packed between the wheels led to immobilized vehicles. I read somewhere about panzertruppen using grenades during the Russian winters to "free up" their vehicles' suspensions after they had been parked overnight.

You wouldn't happen to have a reference to this? I've seen this argument made many times over, but I dont recall it ever being documented in any way (i.e. with a reference to a primary source). The Germans used interleaved suspensions on tens of thousands of vehicles going back to the mid-1930ies, so I'd think that there would be a report or two on mud and ice packing problems - if there were any.

Frankly, I suspect it is an urban legend.

cbo

I jost got through reading "Tigers in the Mud: by Otto Carius, and "Armor Battles of the Waffen-SS" by Willie Fey and neither mentioned this mud packing problem.

Even without mudpacking problems The effort required to replace an inner roadwheel is enormous. Up to 5roadwheels have to be removed to get to an inner wheel. Compared to a conventional system where only the outer wheel of the pair has to be removed (Are inner and outer wheels secured with a single set of bolts and nuts? which would make it even simpler) it seems like a whol lot more work than neccesary in the field.

- bsmart

Even without mudpacking problems The effort required to replace an inner roadwheel is enormous. Up to 5roadwheels have to be removed to get to an inner wheel. Compared to a conventional system where only the outer wheel of the pair has to be removed (Are inner and outer wheels secured with a single set of bolts and nuts? which would make it even simpler) it seems like a whol lot more work than neccesary in the field.

I guess it is a trade off: Great off-road mobility vs a ton of work if you need to replace a wheel (mine damage, for example) or a torsionbar. Probably not much of an issue with the towing vehicles (half-tracks) which pioneered the system, more so with combat vehicles.

Still, the advantage in off-road mobility is significant.

Claus may correct me, but I believe the final drive failure rate would have been much higher for the Panther and Tigers had they not had interleaved and overlapped type suspensions. Reducing MMP reduces the amount of power a tracked vehicle requires to turn on soft ground which means less stress on the transmission and final drive.