Vmo/Mmo on B727's (Current or Fairly Recent) That You've Flown
 

As the B727 still flies :cool:, I'm curious what the Vmo/Mmo is on the version(s) that you fly. I've seen/"heard" ranges from 350/.88 to 390/.9. (Higher speed from original 60's manual)

Vmo was .92 when I was on it back in the early 90's. I'll have to dig out the books to see what the performance envelope was to make that speed.

What a great jet.....

Never had the pleasure to fly her, but I probably sat the JS 50+ times over a 3 year period between RDU and JFK and RDU and MIA.... just plain flying....

There's a selector switch that goes between "A" and "B" with B being the lower numbers. Which is used depends on the loading of the airplane. In most cases I've seen in the past few years, the switch is safety wired to "B". In either setting, the VMO is increased for each 10,000 feet altitude until it matches the MMO. I think all 727s are like this, at least all that I've flown are.

727 speeds
 

Here is from my old 727 manual:
Mode A: VMO - 380 kts at sea level
389 kts at 5000 ft
398 kts. at 10,000 ft., etc.
MMO .90 mach above 21,500 ft.

Mode B: when in-flight weight exceeds 172,000 pounds or ZFW exceeds 136,000 pounds, operate in Mode B for the entire flight.
VMO - 350 kts. at sea level
352 kts. at 5,000 ft.
355 kts. at 10,000 ft., etc.
MMO .90 mach above 26,500 ft.

So there you go. The max takeoff weight of a 727-100 is 160,600 lbs., so it will always be in Mode A. A727-200 could be 178,000 pounds or a -200B could be 190,500 pounds.