The Stinson 108 Voyager Serial Numbers http://personalpages.tdstelme.net/~westin By Larry Westin - February 3, 2007 UPDATED - Rev 00 - 02/03/07 Stinson 108 airframes have serial numbers in 5 locations. AIRPLANE SERIAL NUMBER - Stinson 108's have serial numbers at 5 different locations. The primary serial number for the Stinson 108 is stamped on the steel fuselage frame. Serial numbers are located at the following positions: 1 - The primary airframe serial number is on the copilots side facing the right peddle on the firewall exhaust mount. This number MUST match the serial number on the Data Plate, number 2 below. My thanks to Bob Harper for checking other Stinson 108's to verify the location of the frame serial number. 2 - Stinson Aircraft Data Plate - this is the official Stinson Division of Consolidated Vultee data plate bolted to the inside of the firewall. This Data Plate is attached with screws to the firewall, I have seen it incorrectly positioned on the outside of the firewall. The serial number on the Data Plate and the serial number stamped on the frame MUST match!! This is important!! 3 - Engine Firewall - stamped just below the top of the firewall on the right side (as viewed from the rear). This should match the serial number on the frame (1 above) and fuselage frame (2 above). 4 - Each wing has a serial number on the center flap hinge. 5 - The horizontal stabilizer has a serial number stamped on the horizontal stabilizer spar. To meet current FAA regulations a data plate showing the serial number must also be on the outside of the airplane, generally at the leading edge of the horizontal stabilizer. This is the fuselage serial number. Stinson did not put this plate on the airplane. It is required and available from several companies so the exact location and style vary. IMPORTANT - Stinson did NOT match serial numbers between the fuselage, wings and horizontal stabilizer. However it is important to check all these serial numbers. Normally the fuselage, wing and horizontal stabilizer serial numbers are within about 10 of each other. If you find the difference large, say more than 20, suspect the airplane you are inspecting has been involved in an accident. It may in fact be several different airplanes combined to make a single airplane. There is nothing illegal about using parts from multiple airplanes to make one airplane - HOWEVER it does require substantiating paper work to explain in detail what was accomplished. If you find a large serial number difference then locate the appropriate FAA form 337. If there isn't a FAA form 337 to document the work, then I'd give serious consideration to locating a different airplane to purchase. Horizontal stabilizer serial number - physically a horizontal stabilizer from any Stinson 108 will fit on any other Stinson 108. My reason for emphasizing the horizontal stabilizer serial number is airworthiness directive 47-50-12. If your airplane is serial number 108-4968, and your horizontal stabilizer is also serial number 108-4968 (or close), then AD 47-50-12 does not apply. However if at some point the horizontal stabilizer on airplane 108-4968 was replaced with horizontal stabilizer 108- 2576 (or any stabilizer with serial number 3500 or less), which fits fine, then AD 47-50-12 now applies to your airplane. This is not a major AD, but it needs to be installed if your airplane horizontal stabilizer is serial number 108-3500 or lower. FRANKLIN ENGINE - Note that the airframe Data Plate, serial number 2 above, will also have the serial number of the original Franklin engine installed at the factory. Normally if the engine has been modified to have the heavy case, the original light case engine Data Plate is used and the engine serial number continues to match the engine serial number shown on the airframe Data Plate. Stinson built a total of 2 prototypes and 5,260 production model 108's. Remarkably the serial number for the two prototypes was duplicated for the first two production airplanes. Since the prototypes were dismantled very early into production, there was never a problem with two owners having the same serial number. Later Univair manufactured one model 108-5 which they gave the serial number 108-5001. There was also a model 108-3 with serial number 108-5001. The Univair built 108-5 is no longer on the register so there is no longer a problem of having two Stinson 108 airplanes with the same serial number 108-5001. If you have points I've missed please contact me. Larry Westin, email me at westin@tdstelme.net or to my postal address: Larry Westin 233 Pratt Road Newport, Maine 04953