Here is the surviving example at NASM Garber Facility:

Here are the NASM docent notes on the XB-42:

Douglas XB-43 "Versatile II"

In May of 1943, Douglas proposed a very clean aircraft with a relatively small crew which would require less fuel to achieve desired speed, range, bomb load. Good flying characteristics required and centerline thrust selected. Engines buried within fuselage driving twin propellers at the rear so, if an engine failed, would be no asymmetric trim problems. Douglas aiming at B-29's mission with much smaller aircraft requiring less fuel, 3-man crew, less maintenance, and one-third manhours to produce (vs. B-29).

Bomber, reconnaissance, and attack versions proposed. In early flight tests, stability and vibration problems encountered, especially when snap-open bomb bay doors operated. Second XB-42 crashed near Andrews AFB a few days after setting transcontinental record of 433.6 mph from Long Beach to Washington. Adaptation to jet configuration (XB-43) surprisingly easy as jets were installed in space vacated by Allisons. In this configuration, pressurization problems and temperature changes led to cracking of plexiglas nose and resulted in replacement with rough looking plywood cone.

Plans for production version included replacing 2 bug-eye canopies with single canopy (as on second XB-43). XB-43s performed quite well. Second XB-43 delivered to Muroc Lake May 47 and used as engine test bed. One J35 engine replaced with a GE J47 and was kept flying by cannibalizing first XB-43 which was damaged 1 Feb 51. Late 1953, second XB-43 retired. By then, newer jet bombers were on drawing board (including B-45 and B-47) and USAF dropped further consideration.

Alan Yendle and 'kuhn' guessed Hortens (wonder why? :-) which also loosely fit the criteria, good guess!

Next time I'll pick something that was built in larger numbers :-)  Just have to get creative to make it challenging in the era of Google.

This is great fun guys, thanks.

Over to you Allan.

Gary