Fw/rw atp
Okay, I’ll try to tackle this. Over twenty years ago I had an ATP helicopter and added MEL to it. A bit different then what you are asking but the process should be the same. Let's look at the regs and ask the following questions.
61.159(a)(1) Do you have 500 hours of cross-country time? (Doesn’t matter FW or RW)
61.159(a)(2) Do you have 100 hours of night flight time? (Doesn’t matter FW or RW)
61.159(a)(3) Do you have 75 hours of actual or simulated instrument flight time? (Doesn’t matter FW or RW)
61.159(a)(4) Do you have 250 hours as PIC of airplane? (Airplane time only)
61.159(a) Do you have 1500 hours of total time as a pilot? (Doesn’t matter FW or RW)
It is my understanding that where the regulations specifically says in airplane it has to be airplane time. If it states helicopter, it has to be helicopter time. If it doesn’t state either then both count. I hope this helps.