A life inverted

"Cé hé sin" (michael-m-mouse)
10/27/2020 at 19:04 • Filed to: Inversion, Bats, DB 605

This is a bat. Specifically, it’s some species of fruit bat, or as some in the F ar E ast would call it, “lunch”.

When not flying around it spends its time hanging from its toes. It lives an inverted life then. It sleeps upside down, it leads a busy social life upside down, it conceives little baby bats upside down, it gives birth to little baby bats upside down (actually not so little. Its babies are about one third the weight of their mother. If you’re of the female persuasion, consider delivering a seven year old) and it feeds its little baby bat upside down. Inversion need not stop with death as the toes are so designed that they are held closed by their owner’s weight and so a deceased bat can continue to hang around for some time.

Other things live inverted lives too.

This is a Daimler DB605 as used in WW 2 aircraft . It is not as other engines are.

Traditionally an engine is in this orientation.

Crank at the bottom, head at the top. It’s called a cylinder head for a reason. There are common exceptions such as flat engines and radials and less common ones such as opposed piston designs with a crank at each end and no head.

What’s less common is to turn the whole thing on its head, or heads in this case. Like a bat, the DB 605 spe nt its days inverted. It wasn’t unique in this as several other aero engines did the same. The rea sons why have become somewhat unclear with the passage of time, but the one most commonly mentioned is that by putting the bulky heads at the bottom you could give the pilot better visibility. The reasons why you would not invert your engine are numerous and include the effect of gravity on the oil, which tended to pool in the heads after prolonged inactivity and which being incompressible would do a whole lot of no good. Pre flight preparations included pulling all th e plugs and draining out any oil that had gathered.