Technologies to improve operations
Technologies for operational improvements usually are not directly connected to flight performance. but rather to operating costs. Therefore, simple estimation of their influence is difficult. Most of these technologies are not specifically related to SCT Here, only some of them arc mentioned.
Materials with improved creep resistance for hot engine parts:
In supersonic engines temperatures remain high during cruise, whereas for subsonic aircraft peak temperatures are reached only at take-off. Therefore high temperature creep resistance becomes more important for SCT. It will allow higher engine (cruise) efficiency and/or reduce maintenance costs.
Special control systems to guaranty controllability:
Because SCT-configurations strongly differ from subsonic or military aircraft, some different control problems may occur, e g. •
descent and deceleration to reach sufficient atmospheric pressure levels
• special devices may help to maintain sufficient pressure and temperature in the cabin
If needed, appropriate systems must be developed.
Neutral point and center of pressure vary strongly when going from take-off over transonic flight u> supersonic cruise and back for landing. For optimum flight performance during supersonic cruise, only very small control flap deflections arc allowed.
Both require a highly sophisticated fuel tnm system.
Artificial vision will avoid a Concorde-like droop nose.
Artificial vision is just under development for CAT III landings and ground roll of subsonic aircraft.
Manocuver and gust load alleviation may reduce wing weight.
Just in use for several aircraft (L1011-500. A320, A33Q/A340) and will be improved for future ones (A3XX).
Systems for reduced turn around lime improve aircraft productivity.
Such systems are under development all the time, especially for expensive, very large aircraft like A3XX. Special problems for SCT arc
• a large wuig root blocks accessibility to large parts of the fuselage
• a narrow fuselage retards boarding and ground cabin service (like cleaning)
• the large fuel amount requires several points or long time for fuelling.
Systems to reduce maintenance costs arc under development for subsonic aircraft all the time. Specialities for SCT are
• supersonic inlet and nozzle are specific to SCT
• accessibility to the engines is reduced by supersonic inlet and nozzle, and possibly by installation just at the w ing
• in many areas of the SCT space is very limned (thickness at movables, tail, nose)
• dissimilar SCT-gcomctry requires different procedures
• elevated temperatures dunng cruise introduce dissimilar loads and load cycles which alter maintenance, sometimes even in favor for SCT (e g. corrosion).
Active landing gear allows better damping of roll vibrations, ground loads and supports take-off rotation.
Just under development for very large aircraft like A3XX.
Strongly required are new АТС systems and procedures, especially for long range over-
water guidance and area navigation (direct flight, not restricted to airways linking ATC- control points), and automated data links. They are just under development for subsonic aircraft.
1.4 Technologies for a Concorde Successor: