I find it hard to believe that a Piper Cherokee could do a 13,000+ altitude intercept on a 747 climbing out at 300+ knots/1000 feet per minute.
Well outside it’s performance envelope.
Agreed... it wouldn’t be able to outclimb it. If it were already at altitude with an intercept course that took advantage of the closing speeds. I don’t know. I don’t have my electronic E6B with me.
I also don’t know whether TW800 was still within Class Bravo airspace and/or if it was still restricted to 250 kt. This is all pulled out of very hazy, 20-year-old memories.