Luftmine A (LMA) maximum dropping speed?

[Kari Lumppio]

Hallo!

Does anyone here know Luftmine A (LMA) maximum dropping speed and possible other limitations?

The otherwise excellent document "OP 1673A, German Underwater Ordnance" from 1946 seems not to have this info.


Thanking in advance,
Kari

[edwest2]

Both the Luftmine A and B are referred to here:


"The mines were cylindrical in shape with a hemispherical nose, and deployed under a 27ft diameter green artificial silk parachute, falling at about 40mph. They were fitted with magnetic firing and later with acoustic or magnetic/acoustic firing. When the mine hit the water and sank to more that 8ft, hydrostatic pressure and the disolution of a soluble plug actuated the magnetic device and the mine became operational against shipping. The mine was also armed with a clockwork bomb fuze which caused the bomb to explode when used against land targets, and this was started by the impact of hitting the ground. The mine was timed to detonate 25 seconds after the fuze had started. When deployed at sea, the time fuze did not operate as a diaphragm stopped the clockwork when under the pressure of 7 feet of water or more."

[Kari Lumppio]

Hello!

What I am asking is the maximum flight speed during LMA drop so that the parachute does not break.

OP 1673A:"The Luftwaffe, being unsatisfied with the LM mines because they necessitated low altitude drops at low speeds, pushed the development of their cylindrical, manganese steel bombmines, the BM 1000 series". The frustrating fact is that the source does not give these low speed and altitude values.

Thanks anyway for the interest,
Kari

[edNorth]

And for them not knowing limitations of BM 1000 (600 km/h at 1000 m max), 350 km/h at 50 - 100 m. http://www.deutscheluftwaffe.com/arc...000/BM1000.gif
LMA or B drop speeds seem well buried. I saw on internet today supply 1000 kg containers max drop speed was about 360 km, but Va for Ju 88 A-1 (Mk.I) was at 360 km but minimum safe was about 200 km (wheels up, flaps 0) - Off memory I vaguely remember LMA / B dropping was quite near stalling speed.

[Kari Lumppio]

Thanks EdNorth, very informative illustration.

Cheers,
Kari

[Kari Lumppio]

Tere!

Ise küsin, ise vastan.

After a good lunch did think a second outside of the box: google using German words.

Seems this page has the LMA Abwurf limitations:
http://michaelhiske.de/Wehrmacht/Mar...215/Kap_02.htm

Min height 350 m, maximum not limited
Max flight speed 250 km/h with normal parachute, 400 km/h with lattice type parachute.

Cheers,
Kari