Google and an old WIX post seems to rule out Hudson:
Quote:
denys jones Post subject: Posted: Tue May 24, 2005 7:30 am
Aircraftsman 1st Class
Joined: Sat Oct 16, 2004 7:36 pm
Posts: 7 The parts book for the Hudson calls the tailwheel tyre a Goodyear 17.00 6 ply and assigns it a part number 660070 (the tube is 660004). The mainwheels are called 17-254 Goodyear and p/n 660075 (tube 660001).
I guess this makes the 66xxxx numbers to be Goodyear parts.
I had assumed tyre size might translate to aircraft size implying that the unknown tyre was off something larger than a Hudson?
I thought it may have been the nose wheel tyre for a PBY?, (This is obviously a modern treaded equivalent)

But the manual lists the nose wheel as a Hayes 12 3/8" with a Goodrich 30" smooth contour, which is obviously nearly twice the size of the unknown tyre (and perhaps reflecting that the PBY is nearly twice the size of a hudson smiles).
But this did then cause me to question my understanding of tyre size definitions, and so google yields:
Quote:
AIRCRAFT TYRES
The very earliest of tyre designs were called Type I and were referred to only by their outside diameter eg 27" which is a common fitment to aircraft such as Harvards or P51 Mustangs.
General Aviation tyres are generally Type III designs and include the most widely used sizes such as 5.00-5 and 6.00-6. These measurements refer to the section width of a tyre and also the rim ledge diameter (or the hole in the middle) hence a 6.00-6 is 6 inches wide and sits on 6 inch wheel.
Three Part Name Sizes cover most of today’s designs and typically describe the Outside Diameter, Section Width and Rim Ledge Diameter. Eg, 15x6.00-6, the tyre is 15 inches tall, 6 inches wide and sits on a 6 inch wheel. Some tyres in this classification are preceded with an ‘H’ which identifies the tyre as having a higher percentage deflection.
Metric sizes are the same as three part name sizes but the Overall Diameter and Section Width are replaced with millimeters but the rim sizes remains in inches, eg 380x150-5, it’s imperial equivalent is a 15x6.00-5.
Radial tyres are also the same as three part name sizes but the dash preceding the rim diameter is replaced with the letter ‘R’ eg 32x8.8R16
http://www.speedace.info/tyres_aircraft.htmSo its not Hudson, not A-20, not PBY smiles, - the search continues for what takes a 18" tyre, probably as a tail wheel?
regards
Mark Pilkington