▁ 3 – 4 ▁m ▁and ▁fle w ▁ 7 0 0 – 8 0 0 ▁m . ▁At ▁the ▁second ▁descent , ▁the ▁landing ▁ski ▁col lapsed ▁and ▁the ▁fus el age ▁hit ▁the ▁ground ▁hard . ▁ ▁The ▁pilot ▁seat ▁structure ▁and ▁safety - b elt ▁proved ▁to ▁be ▁very ▁un re li able , ▁because ▁at ▁the ▁end ▁of ▁a ▁rough ▁bra king ▁course ▁Z iese ▁was ▁thrown ▁forward ▁and ▁struck ▁the ▁can opy ▁with ▁his ▁head , ▁losing ▁conscious ness . ▁L uck ily , ▁he ▁wasn ' t ▁seriously ▁injured , ▁and ▁after ▁treatment ▁in ▁hospital ▁he ▁was ▁able ▁to ▁return ▁to ▁flying . ▁Acc ident ▁investigation ▁research ▁team ▁came ▁to ▁the ▁conclusion ▁that ▁the ▁crash ▁was ▁a ▁result ▁of ▁pilot ▁error , ▁who ▁failed ▁to ▁fully ▁release ▁the ▁landing ▁sk id . ▁This ▁accident ▁showed ▁that ▁the ▁aircraft ▁handling ▁was ▁still ▁very ▁un predict able , ▁as ▁a ▁result , ▁all ▁ro cket - power ed ▁fl ights ▁were ▁post pon ed ▁until ▁pil ots ▁were ▁able ▁to ▁effectively ▁control ▁the ▁aircraft ▁in ▁un power ed ▁descent , ▁requiring ▁further ▁gli de ▁fl ights . ▁ ▁The ▁dam aged ▁ 3 4 6 - 1 ▁was ▁later ▁rep a ired ▁and ▁modified ▁to ▁ 3 4 6 - 2 ▁version . ▁It ▁was ▁successfully ▁flow n ▁by ▁test ▁pilot ▁P . K az min ▁in ▁ 1 9 5 0 - 1 9 5 1 ▁winter , ▁but ▁non eth eless ▁these ▁fl ights ▁also ▁ended ▁"