The accident referred to arose out of a moat unusual combination of circumstances in connection with a particular form of apparatus for heating the cockpit from the exhaust. It is unlikely in the extreme that the same kind of accident would happen again, but in view of its possibility and in the interests of safety, I have had the use of this apparatus discontinued pending further experiments which are being undertaken for its improvement. The heating apparatus in use on civil aircraft is of an entirely different design and has given no trouble over a number of years.