▁H . F . ▁Sp it fire ▁variants .) ▁ ▁Car b ure tt ors ▁The ▁original ▁production ▁variants ▁of ▁the ▁Mer lin ▁used ▁an ▁SU ▁manufact ured ▁car b ure tt or ▁in ▁which ▁the ▁fuel ▁flow ▁was ▁meter ed ▁through ▁a ▁float . ▁In ▁most ▁circumstances ▁this ▁proved ▁to ▁be ▁sufficient ▁but ▁during ▁the ▁air ▁batt les ▁over ▁D unk irk ▁and ▁during ▁the ▁Battle ▁of ▁Britain ▁it ▁was ▁found ▁that ▁whenever ▁the ▁Mer lin ▁was ▁subject ed ▁to ▁negative ▁" g " ▁forces , ▁such ▁as ▁a ▁quick ▁" b unt " ▁into ▁a ▁d ive , ▁the ▁engine ▁would ▁briefly ▁lose ▁power ▁through ▁pet rol ▁star v ation . ▁This ▁was ▁because ▁the ▁pet rol ▁in ▁the ▁float ▁was ▁being ▁thrown ▁away ▁from ▁the ▁feed ▁pipe ▁to ▁the ▁super char ger . ▁The ▁fuel ▁inject ed ▁Da im ler - B enz ▁DB ▁ 6 0 1 ▁engine ▁gave ▁the ▁B f ▁ 1 0 9 ▁especially ▁an ▁advantage ▁over ▁the ▁car b ure tt or - equ ipped ▁engine ; ▁no ▁Sp it fire ▁could ▁simply ▁" b unt " ▁and ▁d ive ▁away ▁from ▁an ▁oppon ent ▁as ▁the ▁ 1 0 9 ▁could . ▁The ▁rem edy , ▁invent ed ▁by ▁Be atrice ▁" T illy " ▁Sh illing , ▁was ▁to ▁fit ▁a ▁metal ▁dia ph rag m ▁with ▁a ▁hole ▁in ▁it , ▁across ▁the ▁float ▁ch amb ers . ▁It ▁partly ▁c ured ▁the ▁problem ▁of ▁fuel ▁star v ation ▁in ▁a ▁d