His flying career began in 1930 at the age of 17, when as a co-pilot he accompanied his friend R. N. Chawla to Croydon Airport, London from Karachi in British India, by flight and were the first Indians to do so.

Shortly afterwards, he won the Aga Khan contest for being the first Indian to fly the journey between England and India, solo and within a one-month time frame.

Engineer subsequently joined the Indian Air Force, trained at RAF Cranwell, saw action on the North Western Frontier Provinces (NWFP) and at Burma and as a result was awarded the Distinguished Flying Cross (DFC).

Following retirement, he served as India's ambassador to Iran and later spent time living in California, before his last days in Mumbai.

Aspy, Minoo and Ronnie were recipients of the DFC, a unique feat where three brothers were decorated with gallantry awards.

[3][5] At the age of seven, Engineer witnessed aviators Alcock and Brown make an emergency aircraft landing on the Race Course grounds opposite his father's railway bungalow in Hyderabad, Sindh.

"[5] He completed his early education from the Billimoria Parsi School, Panchgani,[5] and the DJ Science College in Karachi.

[7] On his 17th birthday, his father presented him with a second-hand de Havilland Gipsy Moth and after less than three months of lessons, he obtained his license to fly from the Karachi Aero Club.

[5] In November 1929, the Aga Khan, 48th Imam of the Ismailai sect of Muslims[8] announced a prize of £500[8] to the first Indian who could fly solo between England and India within a one-month time-frame.

[9] Shortly after the announcement, Engineer as co-pilot and his friend R. N. Chawla set on a flight to England in March 1930, at a time lacking radio communications or air traffic control.

On 21 March 1930, they flew into Croydon Airport where the Lord Mayor of London and the press greeted them with garlands.

Tata gave Engineer the spare much needed spark plug which allowed Engineer to complete the journey from Croydon Airport, England, to RAF Drigh Road, Karachi, now in Pakistan, in his Gipsy Moth and was awarded the prize, winning over Man Mohan Singh by one day.

After commanding the airbase for over a year, Engineer was selected to attend the RAF Staff College, Bracknell.

[21] The assets of the Indian Air Force (like other branches of the military) had to be divided between the Dominions of India and Pakistan.

[22][23][24] As the Air Officer Commanding (AOC), he led the group to support ground troops in Jammu and Kashmir during the Indo-Pakistani War of 1947.