И. А. Курбасова Е. И. Силантьева

TEXT В. THE PROBLEM OF INCREASED SPEEDS
(1) How are we going to reach higher speeds on rail­roads? That is really three questions in one for high speeds depend upon the track, the motive power, and the design of the train.

(2) Let us take the motive power first. Both with dies-el and electric power available the average speed of 120 to 160 miles per hour is attainable on long main-line runs over relatively easy gradients (подъем). As the result of constant improvement in design, which includes the utili­zation of very light alloys (сплав), the locomotives have become both more powerful and economical. That is to say, every ton of their own weight provides greater tractive power.

(3) Recent investigations into railway traction have in­dicated, however, that in addition to conventional kinds of traction, air- and magnetically-suspended¹ vehicles are also very promising. % ...

(4) Much importance is now attached to stream-lining locomotives and carriages, which means rounding off and smoothing the locomotives and cars at the front and rear so as to decrease air resistance thereby increasing the speed of running.

(5) As to the track, there are still many obstacles to be overcome to make it suitable for very high speeds. Faster,

heavier and more frequent trains necessitate the use of heavier rails. Nowadays, the engineers give consideration not only to the rail weight but also to the shape (форма) of the rails and the material they are made of. Prestressed concrete is increasingly adopted to make sleepers for mod­ern tracks in order to prolong their life and to increase track stability.

(6) High speeds are unsafe on a line with sharp curves (кривая малого радиуса). The engineers suggest that the latter should be flattened, but the expense of doing it on hundreds of miles would be considerable. So it is neces­sary that the cost of reconstruction should be carefully estimated before it could be decided whether such high speeds would be commercially justified.