GLIDING IN GERMANY GEORQII 277 



Hirth's flight was more difficult and more instructive. He started 

 from the west slope of the Wasserkuppe, and maintained himself 

 there until he had painod 400 m. in height, and then carried out 

 his cross-country flight to the immediate neighborhood of the 

 Schweinsberg without serious difficulty. On the return flight he 

 fomid that he had lost height badly and was 200 m. below the start- 

 ing point. lie was twice forced to turn back and soar over valleys 

 with upwinds in order to regain sufficient height to regain the west- 

 ern slope, over which he cruised until he was high enough to land 

 (m the plateau of the Wasserkuppe at the prescribed point. 



In tiiis admirable exhibition of the methods of cross-country work, 

 it is seen that tlie pilot leaves the original region and seeks new 

 areas of rising wind, leaving nothing to chance, but laying his course 

 beforehand, according to the wind prevailing and to the lay of the 

 land. It is characteristic of such flights that the best course is not 

 in general the shortest distance, but may involve long detours in 

 reaching upwind areas, and lengthy soaring over a particular point 

 in gaining sufficient height. Briefly, the pilot must fly on sound 

 topographical and meteorological information, if he is to reach his 

 goal. Cross-country flights will be achieved over wide regions by 

 flying from slope to slope, from hill to hill, and finally, from range 

 to range. The satisfaction of skillfully adapting soaring flight to 

 the configuration of wind currents and landscape is enhanced, if 

 need be. by the sporting excitement and by the real value to flying. 



Xehring's 1927 flight is another instructive example of cross- 

 country work in which a whole range was traversed by passing from 

 hill to hill. There was no straightforward continuous region of 

 upwinds available. Local areas of rising wind had to be sought 

 out on slopes facing the general direction of the wind, and wide 

 belts of downwind lying between them had to be crossed. The 

 masterly fashion in which Nehring carried out these successive stages 

 is shown on Plate 8. 



A barognim of Xehring's 53 km. flight to Berka, August, 1927, is 

 shown in Plate 9, Figures 1, 2, and a plan and height contour of 

 the same flight in Plate 10, Figure 1. 



The ups and downs of tlie barogram correspond to the up- and 

 downwind regions which were met. The plan of the course shows 

 very well the flying tactics adopted in circling over hills which pro- 

 duced rising winds, long enough to gain extra height for the next 

 stage of the flight. 



Kronfeld's 100 kra. flight in spring, 1929, over the Teutoburger- 

 wald was acliieved by these same tactics, and supports the view tliat 

 a sound knowledge of the flow oi the wind round iiill ranges, liills, 

 knolls, and dunes enables a soaring pilot, competent in his art, to 

 achieve remarkable cross-country performances, over hill and dale. 

 28095—31 10 



