Deployable ballast

 is a miscellaneous item in Fallout: New Vegas.

Characteristics
The Deployable Ballast is a quest item in Fallout: New Vegas, given to the Courier by Loyal at Nellis AFB. It attaches to the B-29 under each wing, between the engines and the propellers. Once detonated, the plane is able to float on the ballasts.

Quests
During Volare!, they have to be put under each wing on the B-29 as said above. Lake Mead is a rad-free but very deep lake, so if you don't feel like chancing it you need to talk to Loyal about getting to the plane. He will send you to his assistant Jack. Jack will say he can help you, but in order to do that, you need to bring him a Pressure cooker, or you can pass a science check to skip this part. If you want a quick find, there should be a pressure cooker in the kitchens there at Nellis AFB. Once you have the cooker, he will give you the Rebreather which allows you to breath underwater. Attach the ballast and complete the quest by going over to the quest marker and activating Loyal's detonator.