HB - Heavy Bomber Aircraft

Model Designation Manufacturer Engine(s) Crew Other
XHB-1
Huff-Daland 1 Packard 2A-2540 4
XHB-2
Fokker-Atlantic 2 Packard 2A-2540
cancelled
XHB-3
Huff-Daland 2 Packard 2A-2540
cancelled