What is a Black Box?

[F2Andy]

I am going through my grandfather's diary of his time in the RFC, in Egypt in 1916, and there are various things he talks about that I cannot fathom. The most important is the Black Box.

This is obviously not what we know as a black box today. It was no on the aeroplane, for one thing. It was large; at one point he is housed in a building; the Black Box is two thirds of it, his quarters he rest. He talks also about a lens, and that may be connected? I get the impression there was only one at the aerodrome - possibly the entire region - and for a while he was the guy responsible for it. At first I thought a dark room, but at one point he says he used it as a dark room, so I guess not. My best guess is that it was a kind of projector room, used for taking data from photographs and putting it on maps?

Other terms:

"archies" - could be anti-aircraft guns

tinder - some kind of road vehicle

volplaned - I am likely misreading this, but something like that, meaning to crash land or make an emergency landing?

bus - a couple of times he refers to the plane (or part of it) as a bus?

[pierssc]

Not sure about the black box - a camera obscura perhaps? Someone will know.

"Archie" is AA fire, a "tender" is a light vehicle.

"volplaned" - not sure. Would gliding with the engine off make sense?  *Yes, google "volplane" = to glide.

A "bus" is an aircraft, also "machine".

Edited 23 October , 2022 by pierssc

[pierssc]

This old thread might assist  re the black box - go to the end

 

[pierssc]

Unfortunately the links in the old GWF thread above are broken.  The "Flight" archive is now at https://archive.org/details/pub_flight-international.  Searching within text for "obscura" brings up some hits, mainly about using one to measure aircraft speed (I haven't read the articles in any depth but I suspect it is unlikely that your grandfather was concerned with measuring precise aircraft speed in Egypt in 1916).  My grandfather's diary/logbook from August/September 1916 in Flanders makes a few references to bombing practice over the camera obscura and it appears to have been located on the aerodrome.  It isn't an easy one to research online but from what I can gather the aeroplane flies along without any actual bombs, but trying to "hit" a practice target.  The aircraft can be seen in the image projected in the blacked out room.  At the moment when the pilot decides to releave the "bomb" he presses eg a Morse key connected to the aircraft's transmitter .  There is a receiver in the camera obscura and the exact position of the aircraft is plotted on the image in the darkened room and then various sums are done on the course, speed, altitude, etc of the aircraft and the characteristics of the notional bomb in order to work out whether or not the "bomb" would have hit the target it was aimed at.  There might be a second camera obscura at a set distance away in order to triangulate it.  It all seems incredibly complicated but it was evidently a useful training tool as it was still used in WW2.  It's great virtue is that nothing is actually dropped so you save money on practice bombs and no one risks getting hurt.

I can't link to it but a PhD thesis entitled "The History and Development of Aircraft Instruments - 1909 to 1919" by John Kirkham Bradley is quite illuminating:  See chapter 3.4 (on p.71).   Air Publication 242 "Notes on Aerial Bombing parts II and III" may also be interesting if one could track it down.

[F2Andy]

20 hours ago, pierssc said:

Not sure about the black box - a camera obscura perhaps? Someone will know.

"Archie" is AA fire, a "tender" is a light vehicle.

The diary definitely says tinder, not tender. Or at least up to a point. in the last few hours I have found the word tender twice, so perhaps he just repeatedly got it wrong (though his spelling is generally excellent).

Camera obscura is kind of what I was thinking about with a projector, though you do have some interesting details. I guess the difference is whether it uses a photograph in the process or not.

I found a link to the Ph.D. thesis by the way: https://spiral.imperial.ac.uk/bitstream/10044/1/8266/1/John_Kirkham_Bradley-1994-PhD-Thesis.pdf

He also talks about EP tents and bell tents. Bell tents are easy, but what are EP tents? They seem to be used for mess.

[pierssc]

Maybe he wrote what he thought he heard (tinder), and later discovered that the word was actually tender. 

The standard Flying Corps tender was made by Crossley.  Search "Crossley Tender" and look at images and you'll find plenty.  In my grandfather's diaries,  the word "tender" appears 19 times, always in connection with motor transport somewhere - moving personnel to and from the squadron, taking them into town for shopping, recreation, or for medical reasons, going out to aircraft which had force landed with mechanics - a general maid-of-all-work.  I said "light vehicle" but "light truck" is probably more apt.

I can't make out whether photographic paper played any part in the process or not.  It may not have been necessary.

I'm afraid I don't know anything about tents, but there is a very useful search box for the forum which you should find in the top right hand corner of the page and using it I found this which may help: