V stands for Navy if I remember correctly. I do not believe it means fixed wing although Navy helo squadrons start with H. VF = Navy Fighter; VA = Navy Attack; VC = Navy Composite; VFA = Navy Fighter/Attack. VM designates a U S Marine squadron
And for Marine Helicopter squadrons... HML-Helicopter Marine Light, HMM-Helicopter Marine Medium, HMH-Helicopter Marine Heavy. I also believe they will throw an "A" at the end of those for "Attack" as appropriate. Such as MHLA for a cobra squadron. A Marine CH-46 pilot told me all those a couple years ago and I'm pretty sure they're all correct.