Aircraft N640 Data

1. - McKinnon serial number "1201" was a completely different airframe. It was originally Grumman JRF-6B s/n 1147 and it was first registered as NC709 with the Fish & Wildlife Service in Alaska. In 1957, McKinnon bought it and converted it into a 4-engine McKinnon G-21C s/n 1201, re-certified under TC 4A24 Section I, and re-registered it as N150M. McKinnon G-21C s/n 1201 ceased to exist as such in June 1960 when McKinnon further modified it, installed a 36-in extension in the nose, added 4 seats, modified the tail slightly, and re-certified N150M as McKinnon G-21D s/n 1251. In 1966, N150M had its 4 piston engines removed and 2 PT6A-20 turbines installed. A year later, McKinnon modified N640 (Grumman JRF-5/G-21A s/n B-123) to have turbines, but it remained certified under Grumman's TC and never officially became a "McKinnon" aircraft at all. Most importantly, McKinnon s/n 1201 and N640 were never the same aircraft - until Larry Teufel falsely started claiming it was in 2001.

2. - As far as McKinnon himself was ever concerned, it remained a Grumman G-21A (s/n B123) certified under ATC-654 but simply modified by McKinnon STCs (which alter the aircraft but not the fact that it was certified under Grumman's TC 654 and NOT under McKinnon's TC 4A24.)

3. - McKinnon never re-certified this aircraft under his own TC (4A24) as far as he was concerned, it was still just a Grumman G-21A (s/n B-123) with McKinnon STCs installed for the turbine engines (STC SA1589WE), the radar nose, the 1-pc windshield, etc. It was improperly re-registered as a "McKinnon" aircraft for the first time in 2001 by the current owner - almost 10 years after McKinnon died.

There is no such thing as a "1944 Grumman/McKinnon Enterprises G-21G" because Grumman built G-21A aircraft under the authority of TC 654 from 1937 until 1945. McKinnon converted some G-21A aircraft into different versions (G-21C, D, E & G) and re-certified them as new aircraft under the authority of TC 4A24 between 1958 and 1970. Once converted and re-certified, the "McKinnon" G-21 aircraft were no longer "Grumman" at all. So, there is no such thing as a Grumman G-21G and there is no such thing as a 1944 McKinnon G-21 of any kind. Furthermore, it is impossible to be both at the same time. AND, the "real" McKinnon serial number "1201" was a model G-21C that ceased to exist in June 1960 - when it became G-21D serial no. 1251. The "current" registration of N640 is completely bogus and invalid!