Armourers selection for DH4 bombload

Graeme has been very helpful on another thread and
perhaps another member could help me with an even more
technical question.
I have read that RFC DH4s typically carried two 112pound
bombs and also could carry twelve 20pound bombs.
I hope that someone has access to an armourers manual or
something equally detailed, and could tell me how the bombloads
were worked out. The mission I am researching involved an
attack on buildings in early 1917 by aircraft of 55 Sqn. RFC.
Three aircraft apparently made it to the target and so I would
like to work out how much explosive they carried to target.

Thanks! LR

[Graeme]

Liam

There were two types of 20-lb bomb available, the Hales that had been introduced in 1914 and the Cooper that replaced it during 1917. The Hales contained only 4.5-lbs of Amatol while the Cooper contained either 4.5-lb of Amatol or 5.4-lb of TNT.

The 112-lb RL (Royal Laboratory) bomb was also a throwback to 1914 and contained either 35-lb of Amatol or 40-lb of TNT.

Source: Bombs Gone by Wing Commander John A MacBean and Major Arthur S Hogben, Patrick Stephens Limited, 1990.

Graeme

Thanks for that information Graeme.
I have just been sorting through some material received
about ten years ago from the flying officer we've been
discussing. The three DH4 aircraft attacked at mid-day from a
height of 12,000 feet. Each carried a load of ten 20lb bombs,
and so that totals thirty bombs scattered over an area I
cannot begin to calculate. The target was a chateau with outbuildings
so the choice would seem appropriate. Were either of the bomb
types you describe classed as "anti-personnel" ? Ack Ack was
"particularly heavy and accurate", but still the surviving aircrew claimed
hits on target. You know the rest of the story. Aircraft lost.
Cheers. LR

[Graeme]

Liam

According to the reference material I have available, the RFC etc used three types of bomb, High Explosive (ranging from the 1914 16-lb RL bomb with 7-lb of TNT to the 1918 3,300-lb SN with 1,500-lb of Amatol), Incendiary (from the 1914 Bomb Petrol Small with 6 pints of petrol, up to the 1918 Incendiary 6.5 oz containing 2.5 oz of Cendite in an Aluminium tube) and a single Anti-Personnel bomb, the 180-lb RL (AP) containing 21-lb of Amatol.

From a height of 12,000 feet I would have thought the chances of hitting a target the size of an individual building with a 20-lb bomb (or even a stick of these) would have been pretty remote - not many machines had previously been able to get that high with a useful bomb load, so aiming techniques were rudimentary.

Perhaps the raid was intended to be more of a gesture, ie that even targets so far behind the German lines were no longer invulnerable, than an actual attempt to take out a military commander. Did Logan express an opinion on the purpose/usefulness of the raid?

Graeme