(1)A letter, return or other document respecting the service of any person in, or the cashiering, dismissal or discharged of any person from, any portion of the Air Force, or respecting the circumstance of any person not having served in, or belonged to, any portion of the Forces, if purporting to be signed by or on behalf of the Central Government or the Chief of the Air Staff, or by any prescribed officer, shall be evidence of the facts stated in such letter, return or other document.
