As regards the first part of the question, the cost of the R.39, which was not completed, was approximately £90,000, and the cost of the R.80 £275,000. As regards the second part, the R.39 was constructed by Messrs. Armstrong, Whitworth, and the R.80 by Messrs. Vickers. As regards the last part, no flights were performed by the R.39, and approximately 73 hours were flown by the R.80.