There are a minimum number of hours specified by Federal Aviation Regulations (FARs) Part 61. I don't know the average now, but the national average used to be about 20 hours over the minimum. Those students who took less than the national average were those who took 3 to 5 lessons a week (some went 7 days).
A rare but very serious risk associated with blood transfusions is transfusion-related acute lung injury (TRALI). It occurs more often with platelets and plasma than with red cells. TRALI is a poorly understood condition, in which a personâs lungs suddenly become very inflamed within six hours of the transfusion.
This could be around 3 to 4 pints of blood, for those keeping track. Blood transfusion is usually necessary with a hemorrhage of this magnitude, according to Alton. âAt this point, the heart will be beating very quickly and is straining to get enough oxygen to tissues,â he said. âBlood pressure drops.