A number of years ago it was discovered that airplanes could suddenly lose a lot of altitude when entering big, mysterious 'air pockets'. It was thought that this was the explanation for a number of mysterious airplane crashes like Eastern Airlines flight 66.

In the beginning no one could believe this phenomenon existed. It was simply not possible that there could be ‘pockets’ in the air or downward airstreams. What was involved was not an ordinary turbulence, but severe pockets in the air, causing sudden plane crashes, (Microbust). The phenomenon has been noticed especially in cases where both the speed and the altitude of an airplane have been low.

We already know that winds inside and around thunderclouds can be unpredictable. Flying into such clouds is not recommended.  But are the strange airplane crash really fully understood ?

According to this theory a extended mass contracts / stretch space especially in its centre. This mean that every thunder cloud have its own field of gravity.

Heavy low pressure of a certain small size are particular dangerous to air traffic, because these are (to a certain extend) small fields of gravity.

If a airplane is exactly in the centre of a small heavy low pressure, a such airplane will certainly become part of a such small field of gravity.

This can most likely cause small heavy low pressure, (included a airplane)  suddenly to lose altitude very quickly, simple because the cloud (included) the airplane suddenly increases its common mass.

Large low pressure are not so dangerous, because these are more fixed to the atmosphere.

This properly sound strange, but we shouldn't exclude this possibility also can play an role.