battle of britain - why no drop tanks?

My understanding is that the luftwaffe were under a big disadvantage as their BF109 only had enough fuel for 10 minutes combat over London. The obvious answer (to us) would have been a drop tank. Any technical reasons why they were not used, or had no one thought of them?

Didn’t they use rocket assisted takeoff which would do about the same thing (provide extra fuel)? And has the advantage of saving a lot of weight = more bombs.

Well, Germany had to conserve metals.
So did we, but we found a very clever way around it.

We developed a technology to coat a cardboard-like material with a thin layer of metal, in a manner similar to electroplating.

As I recall, it was called “metalized cardboard” or “metalized paper”.

This rendered the cardboard impermiable (SP?) to petroleum. It was also very lightweight, & very very cheap.

You do the math.

I think the issue was a matter of the weight of fuel, not the weight of the empty tanks, particularly takeoff weight with a full load of fuel and bombs already.

I think we’re talking about fuel for the fighter escort - bombers weren’t so limited endurance wise. The OP specifically mentions the BF 109, which is a fighter.

That said, if an existing fighter isn’t designed to carry drop tanks, retrofitting one to do so may well give weight/aerodynamics/engineering problems.

You need to have fuel lines going to the drop tanks, pumps to take the fuel from them, a safe reliable quick-release mechanism in case you engage unexpectedly - lots to do, lots to go wrong.

I think drop tanks were an allied idea and didn’t come around until the 8th air force was on the offensive.

The Bf-109E-3 and -4 models used in the Battle of Britain didn’t have mounts for droptanks. They were introduced on the -7 model, which I don’t think was available until early 1941, several months after the Battle.

The Luftwaffe had drop tanks. He-123’s carried them during the Spanish Civil War. But it wasn’t until the later models of the Bf-109 that the capability was adapted to single-engine fighters. The Luftwaffe expected the Bf-110 to be the chief fighter in the Battle of Britain, completely under-estimating the capabilities of the Hurricane and Spitfire. By the time they could have gotten a drop tank designed and produced, the battle was over.

Correction to my post: The droptank-equipped E-7 entered service in Nov 1940, the month after the Battle of Britain is said to have ended. Of course, the Luftwaffe didn’t just give up after October 1940 and droptank-equipped 109s did operate over England into 1941.

Mostly they didn’t have them because they didn’t expect to need them. The Luftwaffe was originally seen as flying artillery providing support for the army as it advanced. Long-range bombing was a very limited task and the bomber escort were supposed to be the Messerschmitt 110. In the event, the Battle of Britian showed that the Luftwaffe was poorly prepared for long range bombing and the Bf 110 couldn’t cut it as a viable escort fighter. The Luftwaffe had to make hasty improvements to the Bf 109 to allow it to carry a drop tank. This wasn’t as simple as it might seem, and involved changing the fuel plumbing, designing a rack to carry the tank, designing a tank that would safely release without striking the aircraft, etc.

thanks for the replies. I guess the war went so fast that they weren’t prepared for it as bookkeeper said

The 109 was a prewar design with a really weak wing. In fact, the wing was the major reason could not keep pace with wartime developments.

More to the point, drop tanks were seen as a sneaky way to turn a fighter into a mere fighter-bomber. The fighter mafia in every air force resisted them in the prewar period. (Why did the Spitfire lack a drop tank? Same, same.)

Further, the need for a fairly long-range escort was not really seen in any air force at the time. The belief then was ‘The bomber will always get through.’ Even with no escort.