| XLB-1 |
|
Huff-Daland |
1 Packard 1A-2540 |
3 |
|
| LB-1 |
|
Huff-Daland |
1 Packard 2A-2540 |
4 |
|
| XLB-2 |
|
Fokker-Atlantic |
2 Pratt & Whitney R-1340 Wasp |
5 |
|
| XLB-3 |
|
Huff-Daland |
2 Liberty V-1410-1 |
5 |
|
| XLB-3A |
|
Keystone |
2 Pratt & Whitney R-1340-1 Wasp |
5 |
|
| XLB-4 |
|
Martin |
2 Pratt & Whitney R-1690-1 Hornet |
|
cancelled |
| XLB-5 |
|
Huff-Daland |
2 Liberty V-1650 |
5 |
|
| LB-5 |
|
Huff-Daland |
2 Liberty V-1650 |
5 |
|
| LB-5A |
|
Keystone |
2 Liberty V-1650 |
5 |
|
| XLB-6 |
|
Keystone |
2 Wright R-1750-1 Cyclone |
5 |
|
| LB-6 |
|
Keystone |
2 Wright R-1750-1 Cyclone |
5 |
|
| LB-7 |
|
Keystone |
2 Pratt & Whitney R-1690-3 Hornet |
5 |
|
| XLB-8 |
|
Keystone |
2 Pratt & Whitney R-1860-3 Hornet |
5 |
|
| XLB-9 |
|
Keystone |
2 Wright R-1750 Cyclone |
5 |
|
| LB-10 |
|
Keystone |
2 Wright R-1750-1 Cyclone |
5 |
|
| LB-10A |
|
Keystone |
2 Pratt & Whitney R-1690-3 Hornet |
5 |
B-3A |
| XLB-11 |
|
Keystone |
2 Wright R-1750-3 Cyclone |
5 |
|
| XLB-11A |
|
Keystone |
2 Wright G1R-1750 Cyclone |
5 |
|
| LB-12 |
|
Keystone |
2 Pratt & Whitney R-1860-1 Hornet |
5 |
|
| LB-13 |
|
Keystone |
2 Pratt & Whitney GR-1690 Hornet |
5 |
Y1B-4, Y1B-6 |
| LB-14 |
|
Keystone |
2 Pratt & Whitney GR-1860 Hornet |
5 |
Y1B-5 |