Tay One-Eleven
I thoroughly researched the subject of the Dee Howard Tay One-Eleven for my book on the One-Eleven (The BAC One-Eleven - the whole story) and reached the following conclusions:
1. Timescale and management: The programme took too long and interested purchasers withdrew. Originally the first flight was due in 1997 but did not happen until 2000.
2. Sales: There were only two orders for the re-engined 400 series. The 500 series version, a better prospect, would require FAA certification and much more testing.
3. Certification: There were still technical difficulties with the structure that needed a substantial BAe input.
4. Company profits: Alenia which took over Dee Howard who were carrying out the programme realised that money could be made more easily and more quickly from the Boeing 727 Tay programme.
5. Partners: Neither BAe nor Rolls-Royce was wholly committed to the programme. The idea of new Romanian-built One-Elevens being powered by Tays never stood much chance of success because the whole ROMBAC operation was working so poorly that no one would have confidence in their supplying new Tay One-Elevens.
Stephen Skinner