Not sure what this is...please help!

[Tommyboy]

Hello
Here are a couple of pics. All i know about it is that it came from a man who worked at Grumman, it's 5'6" long and has "AA5420" stamped on it (blury in picture). I was told this was from an aircraft and not an airboat, but I have doubts about this! I appreciate any light you can shed on this!!!
Thank you,
Tommy

[Dave]

It's almost certainly an airboat prop, and I might be able to find that number. The large bolt holes, squared tips, wide blades and the "AA" drawing number are all consistent with airboat rather than airplane.

[Tommyboy]

Thanks Dave!

Thank you very much for your wisdom, Dave!!!