The court martial which sat at the Air Force Base in Makurdi found Oyebanji and three other executive members of the 151 Base Services Group (151 BSG) Multipurpose Cooperative Society, guilty of misappropriation of over N41 million, property of the cooperative.
Oyebanji, as vice-president of the coop received the stiffest punishment.
Air Commodore Nazib Aliyu,presided over the General Court Martial, which announced its rruling on 24 September.
The three other NAF personnel, arraigned with Oyebanji were: Flight Lieutenant (Flt Lt) Sherifi Olawoore, Flying Officer (Fg Offr) Ademola Adekoya and Warrant Officer (WO) Paul Atteh.
Delivering his judgement, Air Commodore Nazib Aliyu, pronounced the four accused men guilty.
Flt Lt Olawoore was tried for negligently performing his duty as the President of the Cooperative.
His punishment was 6 months loss of seniority.
Flying Officer Adekoya was tried for negligently performing his duty as Secretary of the Cooperative. He was awarded one year loss of seniority.
Oyebanji was tried on a 46-count charge. He was found guilty on all 46 counts and subsequently sentenced to serve 21 years imprisonment.
He also lost a reduction in rank to Corporal and was ordered to refund all monies misappropriated.
WO Paul Atteh, who was tried for negligently performing his duty as the Treasurer of the Cooperative as well as for the Making of False Documents and Criminal Breach of Trust, was found guilty of all 3 charges.
He was awarded reduction in rank from WO to Sergeant, in the first instance, and then eventually reduced to the rank of Corporal.
He is also required to pay a fine of N1,000,000.00. Meanwhile, the GCM has ordered the release of WO Atteh from detention.
While pleading in mitigation, the Defence Counsel urged the Court to show leniency, describing the Accused Persons as first-time offenders.
The sentences were announced as being subject to confirmation by the Appropriate Superior Authority.
However, it is within the rights of the Accused Personnel to appeal the judgment of the GCM, if they are dissatisfied.