HC Deb 16 June 1978 vol 951 cc696-8W
Mr. Kershaw

asked the Secretary of State for Defence how much fuel for its own consumption is loaded into a KC135 tanker aircraft for take-off; and how this load of fuel when added to the 31,000 US gallons which it carries for refuelling other aircraft compares to the fuel load on take-off of a Jumbo jet.

Mr. Wellbeloved

The KC 135 does not carry a separate load of fuel for its own consumption. It can transfer to other aircraft all its fuel load apart from a minimum reserve of 1,200 United States gallons—996 Imperial gallons—and any additional amount needed to reach its own destination.

The aircraft has a total internal capacity of 31,000 United States gallons—25,730 Imperial gallons—but the maximum take-off weight restricts the fuel uplift to 28,770 United States gallons—23,880 Imperial gallons—at the most. However, the KC 135 is not operated at maximum weights in peacetime because this would shorten the aircraft's life. The fuel load carried in peacetime is limited to a maximum of 26,000 United States gallons—21,580 Imperial gallons—but this can be achieved at most military airfields in the United Kingdom only during cold winter weather. Summer temperatures usually limit the load to 22,310 United States gallons—18,520 Imperial gallons. However, even these fuel loads are seldom carried in practice and training missions from the United Kingdom are currently generally flown with fuel loads of 21,550 United States gallons—17,890 Imperial gallons—or less.

By comparison, a Boeing 747–200 can carry about 54,000 United States gallons —45,000 Imperial gallons—of fuel.

Mr. Kershaw

asked the Secretary of State for Defence how many KC135 aircraft have crashed since they were brought into service.

Mr. Mulley

I am informed by the United States Air Force that it has not been possible in the time available to produce figures specifically for the KC 135 before 1970. Since 1970, the KC 135 accident rate has been 0.6 per 100,000 hours. This is between four and five times better than the average for the USAF as a whole.

Mr. Kershaw

asked the Secretary of State for Defence whether he is satisfied that a fully loaded KC135 aircraft can operate safely if two engines fail within five miles of take-off.

Mr. Wellbeloved

Regulations, based on ICAO standards, do not call for any four-engined aircraft to maintain flight at maximum gross weight if two engines should fail on take-off. However, to date there has never been an instance of a KC 135 crashing due to the loss of two engines. In fact, the probability of two engine failure is very remote. As with all similar four-engined jet aircraft, flight can be maintained and a safe landing made on two engines when sufficient speed and altitude have been gained, though in certain circumstances, as with many aircraft, fuel would need to be jettisoned.

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