How come you were in the 744 at that speed? Wouldn't fuel usage be absolutely horrendous?
Fuel use....max continuous thrust in level flight. Yep, it was terrible, but it was better than the alternative. A long time ago now, when I was an FO on the 744. The aircraft max speed is .92, but since the advent of RVSM, everyone has been restricted to .90 mach (which isn't a number many would ever see anyway).
There were a couple of air routes that converged over Ankara in Turkey. It was my habit to listen in on the frequency used by the traffic on the other route, as they would eventually merge with your airway, and in those days the steps were 4000 feet apart....that had the effect of dramatically limiting the traffic that could be handled after the merge. ATC in Ankara would send people up or down as appropriate to make them fit, and if there were enough aircraft, then people would be pulled off the airway entirely, and sent to very low altitudes. But, the way they worked it was a bit different to most ATC units. Instead of juggling the entire stack of aircraft, they would simply REMOVE the offending one...so you could go from being in the high 30s, to the low 20s, or even be pulled off the airway and held. On that particular day, we had an aircraft on the other airway (at the same altitude) with an ETA for Ankara one minute ahead of us, and the lower levels on both airways were already crowded. It was obvious that the quick solution was going to be to pull us off the airway, and send us down to the bottom.
Normally, by working out where the other aircraft were, you could speed up or slow down a bit, to ensure the spacing existed (normally ATC take care of this, but, at this merge, it rarely happened). On this day, slowing wasn't an option. The aircraft that was ahead of us was from an airline that is renowned for not listening out on the radio on the operating frequency, much less a different frequency. So I took the punt that they would have no idea that we existed....in which case if we won the race to Ankara, they'd be sent low, and not me.
Only other time I used .9 in a 747 was just before I left the aircraft. Melbourne ATC were spacing their arrivals, and asked a Thai A340 if he would go a bit faster (I forget the number, but it wasn't fast, perhaps .86)...he said he couldn't and offered something like .83. We were behind him, but jumped in with the offer of .9, so Thai were slowed to about .75, and we got in first.
It's a chess, game...and sometimes quite fun. It is amazing how many airlines have no idea of which aircraft are near them. One mob from just north of here constantly ask for altitudes that are already occupied...
