trk miles consumed in a S/E scenario
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trk miles consumed in a S/E scenario
g'day guys,
Wanting to know: here is the scenario;
for a multi engine aircraft lets say has a 300 FPM rate of climb for a single engine ops scenario and a S/E climb speed of 90 kts, the missed approach started at 1000' AMSL and the missed approach ends at 4000' AMSL which is MSA.
My question is how many nm's over the ground will the aircraft use to get to 4000' AMSL MSA from the 1000' AMSL missed approach point from the instrument approach?
Is there a handy formula to use that will be inter changeable for different aircraft performance catergorys and rate of climb and g/s, but give the same result all the time that is nm's travelled over the ground?
Want to know the rough figures so I have a bit a of knowledge of how many nm's you burn up when you lose a engine!
Thank DW.
Wanting to know: here is the scenario;
for a multi engine aircraft lets say has a 300 FPM rate of climb for a single engine ops scenario and a S/E climb speed of 90 kts, the missed approach started at 1000' AMSL and the missed approach ends at 4000' AMSL which is MSA.
My question is how many nm's over the ground will the aircraft use to get to 4000' AMSL MSA from the 1000' AMSL missed approach point from the instrument approach?
Is there a handy formula to use that will be inter changeable for different aircraft performance catergorys and rate of climb and g/s, but give the same result all the time that is nm's travelled over the ground?
Want to know the rough figures so I have a bit a of knowledge of how many nm's you burn up when you lose a engine!
Thank DW.
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3000ft to climb at 300fpm is 10mins. 10mins at 90kts (1 1/2 nms/min) is 15nm. But i guess it all depends on head wind and tail wind components and if your turning while your climbing or continuing straight ahead.
I just worked this out in my tiny little brain. I may very well be wrong.
I just worked this out in my tiny little brain. I may very well be wrong.
Downwind, it's generally considered bad form to cross post since multiple people end up answering the same question without knowledge of the others. It leads to fractured topics & wastes people's time & effort. For example, this topic of yours has the same answer from three different people in three different forums.
May I suggest a better way? If you're not sure what forum would be best use your judgement & choose one. Post your topic and wait. Sometime answers are few, sometimes many, other times someone will suggest a better forum. You can then close the current thread, leaving link to your new thread in the other forum.
May I suggest a better way? If you're not sure what forum would be best use your judgement & choose one. Post your topic and wait. Sometime answers are few, sometimes many, other times someone will suggest a better forum. You can then close the current thread, leaving link to your new thread in the other forum.
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U say track miles. How many? This way it becomes a case of ft/nm which can then be related to a climb gradient. Then all u do is do look at the dme and make sure u are higher than the prescribed ft/nm. Alternatively a climb gradient on a standard MAP is 2.5%
Also as per the book gradient% = Vert speed/ GS * 1.013
Also as per the book gradient% = Vert speed/ GS * 1.013
Looking at the DME doesn't really help you.
If there are any turns in your escape procedure the DME is immediately out as a means of determining track miles.
Also when you level off to clean up, the reduced rate of climb during this segment makes working out the gradient impossible.
A twin engined aeroplane climbing at gross will climb at 145 ft/nm, or 97 ft/nm if climbing at nett.
In reality the aircraft will probably climb somewhere in between (assuming it took off at the performance limit weight)
When there is a MSA of say 4500 like in Melbourne, most people would round that off to 5000 and you then need to climb 4500 ft (in round figures)
this would take you around 30 track miles - more when you allow for the clean up.
Given most procedure designers would try and keep you within 25 miles to allow you to use the 25 nm MSA printed on the charts you have to have a turn in there somewhere.
It is a bit of a trap because at typical training weights most aeroplanes perform significantly better than the above, and people get a false sense of what the machine can do. Obviously we don't often take off at the limit weight, so we will probably do better than the above figures.
If there is any real terrain around the airport the GPWS is likely to be blaring in your ear because of the differences between the 20.7.1B requirements and the design criteria for GPWS.
Performance is an area that in my opinion is not really properly considered by most people (or companies or management)because it is as boring as bat****, yet we train for engine failures everytime we go into the sim - not doing training at the limit weights is irresponsible in my opinion - I am not saying every simex should be at max weight, but there should be some exposure.
If there are any turns in your escape procedure the DME is immediately out as a means of determining track miles.
Also when you level off to clean up, the reduced rate of climb during this segment makes working out the gradient impossible.
A twin engined aeroplane climbing at gross will climb at 145 ft/nm, or 97 ft/nm if climbing at nett.
In reality the aircraft will probably climb somewhere in between (assuming it took off at the performance limit weight)
When there is a MSA of say 4500 like in Melbourne, most people would round that off to 5000 and you then need to climb 4500 ft (in round figures)
this would take you around 30 track miles - more when you allow for the clean up.
Given most procedure designers would try and keep you within 25 miles to allow you to use the 25 nm MSA printed on the charts you have to have a turn in there somewhere.
It is a bit of a trap because at typical training weights most aeroplanes perform significantly better than the above, and people get a false sense of what the machine can do. Obviously we don't often take off at the limit weight, so we will probably do better than the above figures.
If there is any real terrain around the airport the GPWS is likely to be blaring in your ear because of the differences between the 20.7.1B requirements and the design criteria for GPWS.
Performance is an area that in my opinion is not really properly considered by most people (or companies or management)because it is as boring as bat****, yet we train for engine failures everytime we go into the sim - not doing training at the limit weights is irresponsible in my opinion - I am not saying every simex should be at max weight, but there should be some exposure.
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If it's safe to do so, you could get airborne then fail one and use reduced power on the live one to simulate a full load on perhaps. Then you could get an idea of how things will go if it ever comes to that!
