Which airline does your friend work at? Perhaps at one where the cost index is very low. Many reliable sources give the typical cruising speed to be in the range of M0.80-0.82. Ultimately it varies with cost index - I guess if you want to be accurate you might as well select your cost index and have the cruise speed calculated for you on SimBrief.
While I agree cruising speed could be between .78 and .80, my flight logs from various A330 operators from the past few flights show M.82 or .81. Thus I would say flying .83/.84 would be fairly fast, but .82 is still reasonable.
The Climb/Cruise/Descent profiles (essentially speed) is all directly related to the cost index the airline uses (this is set in the INIT page of the MCDU in the Airbus). Different airlines fly with different cost indexes, hence the cruise speed from airline to airline will vary. Deer’s comment is correct, .78 will probably be a lower cost index (perhaps even zero), whereas .82–84 might be a very high cost index. It’s hard to simply state “[A330] cruises at X speed all the time”. Anywhere from .78 to 82 is reasonable for normal operations, but .78-80 is more common as airlines, for obvious reasons, don’t want to spend more money on fuel for a mere 5-10 minute improvement on their flight time (depending on the flight time length, of course).
Great and informative topic as always :)
Anyone cruise around 0.83-0.85, is this recommend cruising speed?
Too fast as it notes here. Try .78-.80, maybe .81 if you want to go a little quicker.
I’ve cruised at .83 but that would be the max I would cruise with the A330, it could very easily hit some turbulence and overspeed if you went higher than that, I’d recommend anywhere from .79 to .82
it’s quite strange that simbrief regularly recommends FL380+ for ~50% load cruise; always requires 94%+ N1 to maintain M .80 - .82, but i guess simbrief expects this since I often end up with ~5% fuel on arrival
@DeerCrusher You think its time to change it to official lol?
No. lol. Tyler’s will be the official one. 😎
oh yeah right forgot
@DeerCrusher Today I put into practice the data you shared with this amazing unofficial article and helped me have a more reliable flight on long routes. Here you have countless amazing tutorials, but I’m a big fan of your articles that are very enlightening and interesting like others.
Thanks for the feedback Murilo. Really happy to hear that it was of some use to you.
Various online A330 Perf. data constantly has Mach cruise at 0.78 > 0.82
In your checklist it says: Taxi to runway on ENG 1 ( ENG 2 off until departure)
A few weeks ago I sent a long message to the moderators regarding this topic, as it pops up also in the loading screen of IF.
But I will try it again: You do not taxi to the runway for departure on 1 engine on a heavy 2 engine aircraft and you do not taxi on 2 engines on a heavy 4 engine aircraft. If your company allows you, you can switch off 1 Engine on both, the 2 or 4 engine heavy aircraft, after landing.
But again, aircraft like the 330 or any other long range widebody aircraft are just too heavy for a one engine out taxi to the runway.
But here is what the manufacturer of the 330 Itself is saying about this IF procedure (and make your own judgement if it is worth to safe a max of 100 kg of fuel on a 12 min taxi route compared to all the risk factors) :
From the Manufacturer’s Flight Operations Support: Fuel economy, chapter 4: Pre flight procedures, subchapter 4: Taxiing:
[The manufacturer] provides standard procedures in the Flight Crew Operating Manual (FCOM) for such operations [ taxi out on one engine on two engine aircraft or 2 engines on 4 engine aircraft]:
The following factors regarding one or two engine out taxi should be considered carefully prior to its incorporation in the operators standard operating procedures:
- This procedure is not recommended for high gross weights
- This procedure is not recommended for uphill slopes or slippery runways
- No fire protection from ground staff is available when starting engine (s) away from the ramp
- Reduced redundancy increases the risk of loss of braking capability and nose wheel steering.
- FCOM procedures require not less than a defined time (from 2 to 5 minutes depending on the engine) to start the other engine(s) before take off. On engines with a high bypass ratio, warm-up time prior to applying maximum take off thrust has a significant effect on engine life.
- Mechanical problems can occur during start up of the other engine(s), requiring a gate return for maintenance and delaying departure time.
- FCOM procedures require APU start before shutting down the engine after landing, to avoid an electrical transient.
- FCOM procedures require not less than a defined time before shutting down the other engine(s) after landing. On engines with a high bypass ratio, the cool-down time after reverse operation, prior to shut down has a significant effect on engine life.
- If an operator decides to use one or two engine out taxi, then FCOM recommendations about which engine(s) to use should be followed.
As engine-out taxi requires more thrust per engine to taxi and maneuver, caution must be exercised to avoid excessive jet blast and FOD. More thrust is necessary for breakaways and 180 degrees turns.
On twin-engine aircraft slow and/or tight taxi turns in the direction of the operating engine may not be possible at high gross weight.
Single engine taxi may also be considered at low weights to avoid excessive use of the brakes to control the acceleration tendency with all engines. This brake use would be detrimental to carbon brake life.
The following table gives an indication of the advantages of engine out taxi for 8 of the 12 minutes total taxi time, leaving 4 minutes warm up time.
Fuel savings with Engine out taxi
12 minutes taxi (all engines)
12 minutes taxi (8 with engine out)
Engine Out taxi savings
For engine out or all engines taxi, the use of a slow taxi speed costs fuel and time. A burst of power should be used to get the aircraft to taxi speed, then the power should be reduced to idle. However 30kt should not be exceeded.
May I ask, what’s the cruise speed of the A333 in IF? is it 0.82? or 0.78? Google seems to say 0.82
Anything in between! I fly ,80.
I had done A bit of research on this,the cruise speed is between M0.78-M0.82. However,most flights cruise at 0.80 to M0.82,while,say,flights with shorter durations would normally cruise at A lower Mach speed,hope that helped.😉
normally around 0.78-0.80 in real life
Flaps do not need to be full, a high crosswind will effect landing and take off performance it would be better to have a chart
Thanks, so helpful 👍