F-35 Program Executive Officer Lt. Gen. Christopher Bogdan said an engine with the same decibel level of noise as another may be perceived as louder if the character of the noise has a higher or deeper pitched tone. During a press briefing on Oct. 30, Bogdan made an analogy to the F-4 Phantom (see F-35 Noise Good to Go). However, the F-35 engine noise study to which he referred did not compare the F-35’s sound to that of the F-4.
It'll take up to 18 months for Lockheed Martin to deliver the 100 or so F-35s that went directly from production line to storage, awaiting the completion of Tech Refresh 3 testing. Customers haven't complained about the order in which the backlog is being delivered.