In early March 2004, I was visiting my younger brother in Newcastle, NSW and he gave me an aircraft data plate that he had found while cleaning out his back shed. He recalled that I'd brought it home and that he'd seen the plate at our (then) family residence in Newcastle but could not remember the original source of the plate. My recollection of its origin was equally as vague. I did however remember that as a school kid, a mate and I rode our bicycles from Newcastle to Ryhope (a suburb of Newcastle) near Rathmines in the 1950s. During a family outing, I'd seen an old biplane in open storage, so we went out to investigate and photograph the aircraft.

We thought we were photographing a Supermarine Seagull/Walrus. In those days, the airframe was substantially complete, including the tractor engine, although the fabric covered surfaces had seen better days. At the time, I wrote to the Department of Defence seeking information on the aircraft which had the serial, JN200. As you may have gathered by now, it wasn't a Seagull/Walrus but rather one of the three Supermarine Sea Otters that served with the Royal Australian Navy (RAN); the forward fuselage of which is now on display at the Australia's Museum of Flight at Nowra. NSW.

Boys being boys, I can only surmise that the data plate in question 'fell off' this apparently abandoned airframe. The aluminium plate, which is curved as if attached to tubing, is approximately 6.5 cms wide and 5 cms high with attachment extensions either side, is light grey in colour and has the following words engraved in black letters:
WARNINGS
A/C NOT TO BE FLOWN
OFF WATER WITH 'B'
TYPE BOMB INSTALLED
HAVE YOU REMOVED
YOUR HOLDING
DOWN LOCKS?

The fact that the warning states "not to be flown off water with 'B' type bomb installed" led me to believe that the plate came off an amphibian as the statement seemed to suggest that the aircraft could also operate off land. I wrote to the director of Australia's Museum of Flight, Mark Clayton, in the hope that the museum staff may have been able to identify the plate. With the assistance of the curator, the late Lieutenant Commander Bob 'Windy' Geale, the plate was positively identified as belonging to Sea Otter JN200.

After all those intervening years, the data plate was reunited with the airframe (or what's left of it) of JN200. And just what did the warnings on the plate mean? Steve Mackenzie was able to advise that the holding down locks were the locks inserted into the undercarriage mechanism to stop it retracting (i.e. collapsing the airframe) while in use on the ground. They were obviously removed before a flight to enable the gear to be retracted.

'Windy' Geale was able to advise that from memory the bombs were actually smoke floats used to find and measure wind so that the Observer (Navigator) could keep his navigation plot up to date. In those days there were no navigation aids etc and the aircraft depended on very accurate navigation to find its way safely back to the ship. Also, all radio was W/T using Morse code. Windy should remember this type of aircraft - he used to fly them! He also agreed with Steve regarding the locks - if you trundled down a slip way there is no way you would get the wheels up and definitely no way you could take off. As well, it could be a very embarrassing time if you took off from a carrier or ashore with locks in and had to land in the sea.

So, there you have it. A little maritime history and a mystery solved. I am just sorry that my mate and I didn't souvenir the entire airframe. We would now have the only complete Supermarine Sea Otter in the world. (See footnote)

The JN200 Data Plate (Author)

Footnote: The wreck of a Sea Otter has recently been discovered off the coast of Cyprus. The amphibian is apparently relatively complete, nose down in slit at a depth of 155 ft.