Vickers development

Greybeard · 12 June 2009, 03:56 AM

Trying to assemble info about Vickers during its aerial use in WWI.

It looks early one like those fitted on Pup, Tripe, SPAD 7 and Nie.17 had poor rate of fire (450 RPM), further reduced by french synchronizer (Alkan?).

Later, on scouts like Camel and SE-5a, thanks to Hazleton device, rate of fire increased to 850 RPM, not much decreased by Costantinescu synchronizer, while Spandau stuck with rates of fire similar to those of early Vickers.

Is this correct?

In addition, I wonder if late french scouts like Nie.24, Nie.28 and SPAD 13 shared same RAF benefits (CC sync and Hazleton devices) or not.

GB

mossie · 12 June 2009, 04:04 AM

Your best bet on working out information is to refer to Flying Guns WW1 by Anthony Williams, also Early Aircraft Armement by Harry Woodman.

Anthony does visit this site, so specific questions he may answer direct.

Greybeard · 12 June 2009, 12:25 PM

Anthony Williams was already so kind answering to previous questions of mine and I hope it will again in this occasion.

I already read some of his valuable work, as well as much material available on the internet like this very nice treaty at following link:

Firing between the Props

part of an interesting story about Constantinesco's life.

The problem is that lacks a detailed abstract, I think; since here a date is missing... there an info is incomplete (e.g.: Hazleton device when entered service? Was is customary coupled with CC-sync or not? And so on).

I especially would have a reasonably true match of type of aircraft and its Vickers arrangement (850 RPM or slower?). For instance, at above link they state as DH4 entered service with CC-sync and, presumably, highest rate of fire. About this latter, while all sources speak of late high rate of fire as 850 RPM, only one mentions the previous, slower one as 450, but I've also others speaking of 550, so what?

mossie · 12 June 2009, 01:05 PM

Here is another source: Handbook of CC Gear states, on page 4, that:

"With the "C.C." Gear and a properly tuned up Vicker's Gun,
a rate of fire of 600 rounds per minute can be obtained with
no stray shots.
Stray shots are never obtained with this gear if no air
is left in pipe line. The rate of fire varies as gun and trigger
bar movements synchronise or otherwise."

Interesting statements.

Greybeard · 13 June 2009, 02:17 AM

Really interesting, although I would be curious to understand how 600 RPM were obtained.

Thanks for posting these info.

GB

Greybeard · 14 June 2009, 04:05 AM

Sorry, but I'm unable to understand what is stated in CC handbook: if Vickers with Hazelton adapter could fire 850 RPM and CC gave 2400 pulses per minute (see above linked reference) 2400/850= 2.8, which rounded to superior integer is 3, so 2400/3=800 RPM, that's to say a shot every one and half prop rotation.

Why am I wrong?

GB