Not sure what kind of planes are on this old photo? Does anyone have any idea?
This is a formation of Curtiss-Wright AT-9s officially known as the Fledgling, but also known as the Jeep.
A high resolution version of the photo is available here: A formation of AT-9s over the Gulf of Mexico. USAF Photo
The National Museum of the US Air Force has restored an example painted to represent the aircraft in the foreground; more information can be found here: AT-9
That's the Curtis-Wright AT9 Jeep.
It was a trainer aircraft produced between 1941 and 1943.
See more information here: https://en.wikipedia.org/wiki/Curtiss-Wright_AT-9