Can a 2 engines plane takeoff at MTOW when 1 engine quits,or only at lower weight?
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S.B.A.C, Show at Farnborough in 1948 (or was it 49 ?) the Airspeed Ambassador did the enire display with one engine feathered. The weight was not given.
( If the weight had been structurally limited by the limitations of an u/c currently undergoing trials, perhaps that one factor would have reduced the MAUW on the day. Just a thought!)
The power available from a nose wheel is greater than that from most tail wheels.
( If the weight had been structurally limited by the limitations of an u/c currently undergoing trials, perhaps that one factor would have reduced the MAUW on the day. Just a thought!)
The power available from a nose wheel is greater than that from most tail wheels.
Thank you! So the AFM should also tell the MTOW in case of one engine out during the takeoff phase.
Cheers!
Cheers!
If on the day, conditions are challenging: very hot or very low pressure, tail-wind or the runway is contaminated etc, or there is challenging terrain on the climb-out, then the aircraft must not be loaded to MTOW but instead the (lower) RTOW. The RTOW is calculated or checked for every take-off, taking the conditions and locality into account, and the aircraft must not be loaded above this weight.
On something medium sized such as Airbus 320 family, on most days from most international airports, the RTOW will be same as the MTOW, but where the runway or the MET conditions are limiting - for example Gibralter - the RTOW can be tonnes less than the MTOW.
Last edited by Uplinker; 17th Mar 2017 at 11:49.
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Even with ideal Met the RTOW gets limited by LW. MTOW as envisaged here is structural. In ideal condition without any restricting factors OEI is not an issue since it is factored.
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Commercial aircraft must be capable of continuing a take-off if the critical engine fails around V1
ie FAR 25 certifications. The key is the certification basis not whether the aircraft is being used for commercial or non-commercial activities.
On something medium sized such as Airbus 320 family, on most days from most international airports, the RTOW will be same as the MTOW
Depending on the particular aircraft, generally providing that the elevation is somewhere near sea level and the OAT somewhere near ISA. As elevation and/or ISA deviation increase, WAT limits will reduce the weight regardless of runway length, terrain and other considerations.
Even with ideal Met the RTOW gets limited by LW.
This will depend on the difference between TOW and LW and the sector distance. Generally a consideration for shorter sectors.
MTOW as envisaged here is structural.
MTOW will be determined by whatever of the various certification design weight issues results in the lowest weight. Often, but not always, that will be a structural consideration.
In ideal condition without any restricting factors OEI is not an issue since it is factored.
It is not clear what you are referring to here .. perhaps you could amplify your comment ?
ie FAR 25 certifications. The key is the certification basis not whether the aircraft is being used for commercial or non-commercial activities.
On something medium sized such as Airbus 320 family, on most days from most international airports, the RTOW will be same as the MTOW
Depending on the particular aircraft, generally providing that the elevation is somewhere near sea level and the OAT somewhere near ISA. As elevation and/or ISA deviation increase, WAT limits will reduce the weight regardless of runway length, terrain and other considerations.
Even with ideal Met the RTOW gets limited by LW.
This will depend on the difference between TOW and LW and the sector distance. Generally a consideration for shorter sectors.
MTOW as envisaged here is structural.
MTOW will be determined by whatever of the various certification design weight issues results in the lowest weight. Often, but not always, that will be a structural consideration.
In ideal condition without any restricting factors OEI is not an issue since it is factored.
It is not clear what you are referring to here .. perhaps you could amplify your comment ?
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n ideal condition without any restricting factors OEI is not an issue since it is factored.
If you see a typical RTOW chart with a long runway, no obstacles in lower temperature range the MTOW matches structural and RTOW caters for performance after engine failure after V1.
If you see a typical RTOW chart with a long runway, no obstacles in lower temperature range the MTOW matches structural and RTOW caters for performance after engine failure after V1.
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If you see a typical RTOW chart with a long runway,
I think you are saying that WAT limits are the consideration ?
But what is factored in your story ?
I think you are saying that WAT limits are the consideration ?
But what is factored in your story ?
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I meant if the chart throws up RTOW equal to MTOW then one engine performance is also considered as a part of the calculation. It will be able to take off and meet gradient requirements.
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MaverickSU355
Remember the wings have to fly in that OAT also, so a higher inertial speed (GS) is needed for V1 V2 etc. So higher temp, thrust is less, acceleration is slower, and with a higher GS required, the runway needs to be longer on two counts.
. . . for a near sea level altitude and for an air of no more than 35 Celsius (cooler air gives more engine thrust), . .
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I meant if the chart throws up RTOW equal to MTOW then one engine performance is also considered as a part of the calculation.
Both AEO and OEI performance is considered for EVERY takeoff. Whichever of the various calculations gives the least TOW for the day becomes the limiting case.
You can't read anything regarding this process into whether the RTOW is equal to, or less than, the MTOW.
It will be able to take off and meet gradient requirements.
This will apply ALL the time, regardless of which limit results in the particular RTOW.
Both AEO and OEI performance is considered for EVERY takeoff. Whichever of the various calculations gives the least TOW for the day becomes the limiting case.
You can't read anything regarding this process into whether the RTOW is equal to, or less than, the MTOW.
It will be able to take off and meet gradient requirements.
This will apply ALL the time, regardless of which limit results in the particular RTOW.
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May be factored was wrong choice of word considered would have been more appropriate. Going back to the OP the answer is since there are no adverse factors the answer is simple yes it can take off at MTOW with OEI.
In the scenario described if Max ToW is equal to the RTOW then the plane would be ok to takeoff provided appropriate WAT limits apply for the following
1. Obstacles
2.second segment critical climb
On a particular runway
WAT limits for the ASDA, TORA and TODA and NTOFP must be met if they are, then RTOW can match MTOW
1. Obstacles
2.second segment critical climb
On a particular runway
WAT limits for the ASDA, TORA and TODA and NTOFP must be met if they are, then RTOW can match MTOW
Last edited by Pugilistic Animus; 20th Mar 2017 at 12:55.
As TangoAlphad also picked up on, the OP is obviously not a pilot ! If s/he was, s/he would know the answer to their question.
Hence why quoting FAR 25, and WAT limits etc is probably too much detail for them and why I gave a very simple generalised answer.
Tango probably explained it better than I did.
Hence why quoting FAR 25, and WAT limits etc is probably too much detail for them and why I gave a very simple generalised answer.
Tango probably explained it better than I did.
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In the end we can all just fall back on the simple logic... no point of certifying a structural MTOW that can not be used as RTOW in normal (i.e. not extremely favourable) conditions.
That'd just be flushing money down the drain.
That'd just be flushing money down the drain.
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The Ambassador mentioned in #23 in 1949 took off in front of the crowd,using but a fraction of Farnborough's long runway. WAT limits may not have made things difficult.
Blackbushe was near and available. It was used on the days for Guests,(like my employer ) rather than get in the way of the SBAC show. IIRC, after landing the Ambassador did a short single engine reverse taxy.
Little performance information other than " The Limitations" would be made available to me as a F/O or as a Captain until 1962 when the airline which I joined had bought a Photocopier before their first aircraft !
Blackbushe was near and available. It was used on the days for Guests,(like my employer ) rather than get in the way of the SBAC show. IIRC, after landing the Ambassador did a short single engine reverse taxy.
Little performance information other than " The Limitations" would be made available to me as a F/O or as a Captain until 1962 when the airline which I joined had bought a Photocopier before their first aircraft !
Last edited by Linktrained; 27th Mar 2017 at 00:06.
When I did my ATPL in the early 1990s, we spoke of MTOM - mass - not weight, as weight is a function of mass and gravitational force. So both from an engineering and physics perspective, speaking of mass is more accurate than weight which varies depending on your location (albeit by tiny amounts). I'm surprised to see that not a single one of you commenters here is using mass. Has this changed in the syllabi to use weight?
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I'm surprised to see that not a single one of you commenters here is using mass.
In industry practice, both terms are used interchangeably, albeit incorrectly. Functionally, it matters little .. just a little "g" here and there in the equations ..
But you are quite correct, we should refer to mass. I don't see that happening across the board any time soon, though.
In industry practice, both terms are used interchangeably, albeit incorrectly. Functionally, it matters little .. just a little "g" here and there in the equations ..
But you are quite correct, we should refer to mass. I don't see that happening across the board any time soon, though.
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Going back to the OP the answer is since there are no adverse factors the answer is simple yes it can take off at MTOW with OEI.
First off, the criteria has NO CRITERIA OEI DEP It is up to the airline to determine what the take off weight is, by looking at runway length, engine performance (which varies in time), elevation, and especially temperature.
MTOW listed, is based on engine performance (new), the airport at sea level, at 15 degrees C. Vary the engine, altitude, or temperature from 15, and it varies significantly.
Luckily, back at HQ, the performance people who are loading the ac have this sorted out for both DEP, DEP OEI, ARR, and ARR missed.
Do you also feel that you can simply use the same DEP procedure when OEI?
Are you aware that there is no criteria for OEI flightpath (see above) and that simply using what is on the chart (unless spec as OEI) offers no protection unless you can meet that climb rate, to which the pilot does not have the means to calculate?
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Didn't someone actually do this in a Twin Otter?
There are some stories .. run a search in PPRuNe .. there was a thread I can recall on the subject
.. but the Aero Commander marketing exercise did occur and involved removing one prop and then flying a lengthy OEI flight.
There are some stories .. run a search in PPRuNe .. there was a thread I can recall on the subject
.. but the Aero Commander marketing exercise did occur and involved removing one prop and then flying a lengthy OEI flight.
Single engine take off in a BK117C
