12 P.SATRE J.AIRCRAFT 为txtro journey time to the CONCORDE effort.The collaboration between the United States and Europe is already widespread in the field of engines and equipment;I hope it will soon exteud to the aircraft as well. 100 But it is not enough to keep building more advanced aireraft.Ground facilities,and airports in particular,must also keep pace.There can be no question of accepting as Supersonic permanent the holding constraints currently being imposed on aircraft at certain airports. 50 objective This is no easy problem,as we are well aware,but it must Subsonic absolutely be solved at all costs.We find it difficult not to compare the stringency of the noise level reduction proj- ects with the looseness of many of the projeets for dealing 0 Extra journey time(hours) with ground facilities and air traffic control.The former 0 2 are too severe,the latter not sufficiently so. Fig.20 Effect of extra journey time (transatlantic My personal conviction is that neither of these problems journey). can be resolved by a stroke of magic-no more the noise problem than the congestion problem.Both are going to require patient effort and a start has been made by all con- 3 hr and 45 min,i.e.,at a block speed of 80 mph,on an air- cerned.What are needed simply are directives and reason- craft which was supposed to fly at 500 mph. able time limits.The trait specific to SSTs in both eases is their marked sensitivity,which heightens the disadvantages Conclusion of whatever constraints are imposed. However,I feel confident that the efforts of aireraft manu- What must we conclude from this review of the SST's facturers and the authorities will converge toward reason- problems?In the first place,much still remains to be done able compromises that will result in a gradual improvement by the aireraft constructors.Our task is all the more fas of the present situation,yet remain compatible with poten- cinating because we are very far from having solved all our tial technical advances. problems.And in any event,the era of supersonic aviation And while we hesitate to become involved in problems is close at hand.As I have said,our current difficulties are which either siniply do not exist or have beeu incorreetly precisely those in which we also place greatest hope:if stated,we are ready to cooperate to the best of our ability to a loss of 1%fuel consumption means a 5%loss in payload, solve the two problems I just mentioned,or any real problem then a 1%gain on fuel consumption must mean a 5%gain for that matter. in payload. In the last few years,the misconceptions entertained about About the progress of aircraft,I gladly note,which my the SS'T have often been highlighted at the expense of its presence here today shows once more,the atmosphere of true problems.I thank you for the opportunity you offered cooperation existing in the western world.And I wish to me to review all these problems,and to express my confidence convey my thanks to the U.S.industry for its contribution in the brilliant future of supersonic transport.12 P. SATRE J. AIRCRAFT Fig. 20 Effect of extra journey time (transatlantic journey). 3 hr and 45 min, i.e., at a block speed of 80 mph, on an air￾craft which was supposed to fly at 500 mph. Conclusion What must we conclude from this review of the SST's problems? In the first place, much still remains to be done by the aircraft constructors. Our task is all the more fas￾cinating because we are very far from having solved all our problems. And in any event, the era of supersonic aviation is close at hand. As I have said, our current difficulties are precisely those in which we also place greatest hope: if a loss of 1% fuel consumption means a 5% loss in payload, then a 1% gain on fuel consumption must mean a 5% gain in payload. About the progress of aircraft, I gladly note, which my presence here today shows once more, the atmosphere of cooperation existing in the western world. And I wish to convey my thanks to the U.S. industry for its contribution to the CONCORDE effort, The collaboration between the United States and Europe is already widespread in the field of engines and equipment; I hope it will soon extend to the aircraft as well. But it is not enough to keep building more advanced aircraft. Ground facilities, and airports in particular, must also keep pace. There can be no question of accepting as permanent the holding constraints currently being imposed on aircraft at certain airports. This is no easy problem, as we are well aware, but it must absolutely be solved at all costs. We find it difficult not to compare the stringency of the noise level reduction proj￾ects with the looseness of many of the projects for dealing with ground facilities and air traffic control. The former are too severe, the latter not sufficiently so. My personal conviction is that neither of these problems can be resolved by a stroke of magic—no more the noise problem than the congestion problem. Both are going to require patient effort and a start has been made by all con￾cerned. What are needed simply are directives and reason￾able time limits. The trait specific to SSTs in both cases is their marked sensitivity, which heightens the disadvantages of whatever constraints are imposed. However, I feel confident that the efforts of aircraft manu￾facturers and the authorities will converge toward reason￾able compromises that will result in a gradual improvement of the present situation, yet remain compatible with poten￾tial technical advances. And while we hesitate to become involved in problems which either simply do not exist or have been incorrectly stated, we are ready to cooperate to the best of our ability to solve the two problems I just mentioned, or any real problem for that matter. In the last few years, the misconceptions entertained about the SST have often been highlighted at the expense of its true problems. I thank you for the opportunity you offered me to review all these problems, and to express my confidence in the brilliant future of supersonic transport