 The XBTM @-@ 1 was a low @-@ winged , all @-@ metal monoplane with folding wings to allow more compact storage in carrier hangar decks and conventional landing gear . Its fuselage was an oval @-@ shaped stressed @-@ skin semi @-@ monocoque with the single @-@ seat cockpit and its teardrop @-@ shaped canopy positioned just aft of the air @-@ cooled engine . Just behind the cockpit was a 150 @-@ US @-@ gallon ( 570 l ; 120 imp gal ) fuel tank . The large wing consisted of a two @-@ spar center section with hydraulically @-@ folded three @-@ spar outer panels . A large dive brake was positioned on the trailing edge of the wing . When closed it could be lowered for use as a landing flap or it could be split into alternating upper and lower section with inter @-@ meshing " fingers " for use in its intended role . It was very effective in this role , mainly due to its great surface area , but this was at the cost of the width of the ailerons , which significantly reduced their efficiency . A pair of 180 @-@ US @-@ gallon ( 680 l ; 150 imp gal ) fuel tanks were positioned in the roots of the center section . All fuel tanks were self sealing and the pilot and oil cooler were protected by 297 pounds ( 135 kg ) of armor . 
