The source, who asked not to be named because he was not authorized to speak on the issue, said the Navy has already forwarded the request letter to the Air Force requesting for expertise in fleet supervision and operations.
Kaduna State Governor Patrick Yakowa, ex-National Security Adviser General Andrew Azazi and four others died in the crash while returning from the burial of the father of a presidential aide, Oronto Douglas.
The internal probe is coming a day after the Chief of Naval Staff, Vice Admiral Dele Ezeoba, has set up a board of inquiry to investigate the remote and immediate causes of the crash of the helicopter.
The Chief of Training and Operations, Rear Admiral Emmanuel Ogbor, said Monday that members of the board included aircraft investigation specialists, AgustaWestland-the manufacturers of the aircraft-and other aviation regulatory agencies as provided by extant regulations.
The in-house investigation may not be unconnected with the alleged misuse of aircraft in the naval fleet. The source said even though the Navy has set up a panel, it required the assistance of the Air Force to help it handle some of the internal hiccups.
"The naval aviation is young in Nigeria and requires some experience to handle some of the issues like this one. The probe is also in line with military aviation procedure as some of the findings may affect the career of those who did or did not do what led to the situation," the source said.
However, Ogbor has dismissed insinuations that the helicopter was not airworthy before it crashed, adding that only investigation would determine the cause.
Navy spokesman Commodore Kabir Aliyu and his Air Force counterpart Air Commodore Yusuf Anas declined comments.