Also, it's a 90 gallon tank. I don't know if it's US or imperial. The gauge is in pounds and usually says between 480 and 500 when the tank is full. I would have no doubts if you told me the AV8A had a 60 imp gal tank.
500 lbs is right, the rest is wrong. 500 lbs is 227 KG which is 50 Imperial or about 60 US gallons. The 90 second duration was correct.