Mods and changes

[Gregory]

During WW2, the Macchi fighter family was the subject of about 300 modifications, mostly incorporated in the field.

I would like to understand how this number compares with other comparable aircraft. Can anyone shed any light on this little documented subject?

Gregory

[Randy Haskin]

It depends on what you mean by "moifications". In the USAF we have what are called "Time Compliance Technical Orders", which could be anything from a major airframe modification (like the new intakes and engine nozzles on the T-38C) to a simple inspection. Often TCTOs might involve changing a bolt, or replacing a type of instrument, or changing a flight control actuator, etc. So, are these "modifications"?

These kinds of things happen all the time during the lifetime of an operational airplane. 300 seems like a lot over a short time frame (if those minor changes are what we're referring to), but it probably isn't all that unusual.

[Ollie]

Randy, those TCTOs are like Airworthiness Directives for the civvies, right?

Gregory, the Bf 109 must have been the one with the most modifications. Just try to follow what version is which serial number and you get mad.

The Fw 190 must be high on the list too!

[Randy Haskin]

Randy, those TCTOs are like Airworthiness Directives for the civvies, right?

Yes, that's pretty much the same thing.