How does hobby interest since 1955, dedicated historian since 1965 and working with the industry for the best part of 25 years strike you as regards to "long enough"?
Apart from which, by definition you are still wrong.
As I said in previous posts, corporate aircraft which are designed from the ground up as business tools for executives (e.g. Dassault, Grumman, Lear etc.) are corporate aircraft.. The A319CJ and BBJ can also be classed as corporate jets as, whilst derived from airliner designs, they have been modified and marketed as a different aircraft due to performance and other factors being changed in the basic design and are different enough from the airliner for the manufacturer to differentiate by designation and certification.
As for the Boeing and Douglas/MDD airliners delivered to private individuals/business house customers (and, of course for heads of state) your list is very short compared to the actual numbers built For instance how about the various Boeing and MDD aircraft for the Saudi Royal Family?.
You can also throw in BAC 1-11s, the odd Caravelle, a certain Saudi Comet, not to mention various Airbus types - all of which were built for non airline customers but all came down the line as standard airframes and were subject to changes at periods during build and were then sent away for major work at specialist companies who fitted the interiors, tweaked the performance or just put on a special paint scheme.
At no time did any of the manufacturers claim these were, or are, corporate jets as distinct from airliners. They acknowledge them as standard aircraft used for corporate purposes.
Even the two USAF Presidential 747s are listed by Boeing as B747-2G4B - which is how they left the line. The extensive work carried out afterwards was classed as a customer conversion.
It's a fine but accurate differentiation.
Last edited by philbky; 4th Apr 2009 at 18:59.