The aircraft was still experiencing extensive teething troubles as well as being victimized by "urban legends", mostly involving inapplicable twin engine factors which had been designed out of the aircraft by Lockheed. In addition to these, the early versions had a reputation as a "widow maker" as it could enter an unrecoverable dive due to a sonic surface effect at high sub-sonic speeds. The 527 P-38Fs were heavier, with more powerful engines that used more fuel, and were unpopular in the air war in Northern Europe. Since the heavier engines were having reliability problems and with them, without external fuel tanks, the range of the P-38F was reduced, and since drop tanks themselves were in short supply as the fortunes in the Battle of the Atlantic had not yet swung the Allies' way, the aircraft became relatively unpopular in minds of the bomber command planning staffs despite being the longest ranged fighter first available to the 8th Air Force in sufficient numbers for long range escort duties. Nonetheless, General Spaatz, then commander of the 8th Air Force in the UK, said of the P-38F: "I'd rather have an airplane that goes like hell and has a few things wrong with it, than one that won't go like hell and has a few things wrong with it."