Hey guys,
MTOW = 45000 lbs
MLW = 40000 lbs
MZFW= 36,200 lbs
Flight fuel = 4000 lbs
Reserve FUel = 800 lbs
Empty weight = 20000 lbs
Find the PAyload ?
PayLoad
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200hr Wonder
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fly1_777
OK I am going to go out on a bit of a limb here, sounds like you are studying for an exam, IATRA, CPL, what ever it happens to be. It also seems like you have one of them nifty question books and you are going through it. Please stop put that book away for roughly the next month and study FTGU, AIM, Air Command Weather Manual and what ever other reference books you have. Go through each from cover to cover, make notes, review the notes, then when you have most of the info in your head go and write the sample exams in the book and write each exam as if it where an exam. Give your self three hours and use only the equipment and material you would get in a TC exam. Then when you are done for each incorrect answer go back and review the ENTIRE section of what you got wrong. Wash rinse repeat until you get 90%+
Then I will guarantee a pass on what ever exam you are studying for. Just going through an exam question and answer book will leave out roughly 50% of the important stuff you need to know. Then after taking my advice into consideration if you are having problems with a topic or have questions feel free to post them and the nice people around her will be more than happy to help you out.
Cheers,
200hr Wonder
And no I am not trying to flame you I am trying to give you good advice to passing whatever exam it is you are trying to write.
OK I am going to go out on a bit of a limb here, sounds like you are studying for an exam, IATRA, CPL, what ever it happens to be. It also seems like you have one of them nifty question books and you are going through it. Please stop put that book away for roughly the next month and study FTGU, AIM, Air Command Weather Manual and what ever other reference books you have. Go through each from cover to cover, make notes, review the notes, then when you have most of the info in your head go and write the sample exams in the book and write each exam as if it where an exam. Give your self three hours and use only the equipment and material you would get in a TC exam. Then when you are done for each incorrect answer go back and review the ENTIRE section of what you got wrong. Wash rinse repeat until you get 90%+
Then I will guarantee a pass on what ever exam you are studying for. Just going through an exam question and answer book will leave out roughly 50% of the important stuff you need to know. Then after taking my advice into consideration if you are having problems with a topic or have questions feel free to post them and the nice people around her will be more than happy to help you out.
Cheers,
200hr Wonder
And no I am not trying to flame you I am trying to give you good advice to passing whatever exam it is you are trying to write.
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mellow_pilot
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Yeah, you really don't want to just do the practise exam. If your groundschool was incomplete or you don't study enough, you're garunteed to see new stuff on the TC exam.
There is no replcement for knowledge. Think of it this way, if you're in the air with ice building on your wings and limited feul, it's better to know the answer to a question for sure, than to look it up. It's not just about the test.
There is no replcement for knowledge. Think of it this way, if you're in the air with ice building on your wings and limited feul, it's better to know the answer to a question for sure, than to look it up. It's not just about the test.
Dyslexics of the world... UNTIE!
I would say your payload is 16,200 lbs. Remember your MZFW is 36,200 lbs. and your empty weight is 20,000 lbs. Even though you are carrying only 4,800 lbs of fuel you still cannot load the aircraft with payload beyond your Maximum Zero Fuel Weight.
You Can Love An Airplane All You Want, But Remember, It Will Never Love You Back!
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Chuck_123go
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The answer to your question is 16,200lbs.
You are using Transport Category Aircraft weights so while we are here we might want to clear up a few things. I will use Boeing 737 terms. Each manufacturer uses their own, but in the end they are all the same.
Crazymax is correct in his/her assertions, but only as they apply to small aircraft with no MZFW. With bigger aircraft it is a bit more complicated.
(For the newbies, MZFW ,Maximum Zero Fuel Weight, is the maximum an aircraft can weigh with no fuel. Weights above MZFW must be because of fuel.)
The MTOW given is I assume Maximum Structural TOW, because on any given flight with aircraft this size the MTOW varies.
How?
MTOW for your flight may be limited by your structure limits (S), landing weight (L), runway performance (Field) (F), climb performance (C), brake energy limits (for a rejected takeoff) (B), or MZFW (Z), to name but a few.
MTOW (S) is a legal limit.
MTOW (L) is based on Trip Fuel and is MLW + Trip Fuel. This is normally the very first thing you calculate because if it is less than your MTOW(S) then it is more limiting and you must use it for any further calculations. MLW may also change because of the size or condition of the landing runway. In that case MTOW (L) would be MLW (performance) + Trip Fuel.
MTOW (F,C,B,) are performance limits which may influence your payload by using different flap settings, time of day for takeoff (cooler temps), longer runways or runways with no obstacles.
Of course if you are in the boonies and spears, arrows and bullets start bouncing off your aircraft all this goes for a dump and MTOW calculations tend to be along the lines of “Let’s get the f--- out of here. Man I hope it clears those trees…”
In your example I will assume unlimited runway, no minimum climb gradient and that the question isn’t a trick one of “yes, but the CARs say that I need xxx of fuel because of xxx, soooo we will have to adjust our fuel and therefore our weights by…..”
If you were to take off at the MTOW(S) of 45,000, you would be overweight on landing by 1,000 lbs. (45000-4000=41000).
MLW of 40,000 + 4000 Flight Fuel (also commonly called Trip Fuel) gives a MTOW of 44,000 (L).
44,000 lbs is your MTOW for this flight as limited by your landing weight, MTOW (L)
In this example MTOW (L) - Total Fuel (4000 +800) = 39,200. This is 3,000 lbs more than your MZFW of 36,200 so maximum cargo is:
36,200 -20,000 =16,200 lbs can be carried.
You could carry that left over 3,000 lbs in more fuel if you wanted. Remember though, all weight above MZFW must be because of fuel.
One of the wrong answers on the test will be 19,200. (MTOW (L) – total fuel – empty weight 44000-4800-20000 = 19,200) to see if you grasp that concept. The other wrong answer will be 20,200 lbs. (20,000 + 4,000 +800 =24,800…45,000-24,800=20,200 lbs.) That would be using Crazymax’s example. Correct as it is for small aircraft, it doesn’t work here because of the MZFW.
If, for the sake of argument, your aircraft could carry 15,000 lbs of fuel, you went with full tanks and your Trip fuel was 10,000, then:
40,000 (MLW) + 10,000 (Trip Fuel) = 50,000 lbs. 50000> 45000 MTOW(S) so Landing weight is not a limitation and we can use our full Structural weight. Our landing weight will be 45,000 -10,000 = 35,000 lbs.
45,000 MTOW(S) - 36200 (MZFW) = 8,800 lbs of fuel available to carry a full payload. As we have 15,000 of fuel it is obvious that we are going to have to eat into our available payload to be able to carry that fuel.
45,000-15,000 = 30,000 lbs. 30,000-20,000 (Empty) = 10,000 lbs available payload. Or if you like we “ate” 6,200 lbs of available pay load.
And payload in a commercial operation is just like the name implies, it is the load that pays for the flight. That little tidbit is often lost on people.
So now you have to decide what is more important, getting to your destination non stop in which case you are limited to 10,000 lbs payload
OR
Carrying as much payload as you can in which case you are limited to 8,800 lbs of fuel Max. and stopping to fuel somewhere with the increased costs of added flight time, possible landing fees etc.
Good luck on you exam!
You are using Transport Category Aircraft weights so while we are here we might want to clear up a few things. I will use Boeing 737 terms. Each manufacturer uses their own, but in the end they are all the same.
Crazymax is correct in his/her assertions, but only as they apply to small aircraft with no MZFW. With bigger aircraft it is a bit more complicated.
(For the newbies, MZFW ,Maximum Zero Fuel Weight, is the maximum an aircraft can weigh with no fuel. Weights above MZFW must be because of fuel.)
The MTOW given is I assume Maximum Structural TOW, because on any given flight with aircraft this size the MTOW varies.
How?
MTOW for your flight may be limited by your structure limits (S), landing weight (L), runway performance (Field) (F), climb performance (C), brake energy limits (for a rejected takeoff) (B), or MZFW (Z), to name but a few.
MTOW (S) is a legal limit.
MTOW (L) is based on Trip Fuel and is MLW + Trip Fuel. This is normally the very first thing you calculate because if it is less than your MTOW(S) then it is more limiting and you must use it for any further calculations. MLW may also change because of the size or condition of the landing runway. In that case MTOW (L) would be MLW (performance) + Trip Fuel.
MTOW (F,C,B,) are performance limits which may influence your payload by using different flap settings, time of day for takeoff (cooler temps), longer runways or runways with no obstacles.
Of course if you are in the boonies and spears, arrows and bullets start bouncing off your aircraft all this goes for a dump and MTOW calculations tend to be along the lines of “Let’s get the f--- out of here. Man I hope it clears those trees…”
In your example I will assume unlimited runway, no minimum climb gradient and that the question isn’t a trick one of “yes, but the CARs say that I need xxx of fuel because of xxx, soooo we will have to adjust our fuel and therefore our weights by…..”
If you were to take off at the MTOW(S) of 45,000, you would be overweight on landing by 1,000 lbs. (45000-4000=41000).
MLW of 40,000 + 4000 Flight Fuel (also commonly called Trip Fuel) gives a MTOW of 44,000 (L).
44,000 lbs is your MTOW for this flight as limited by your landing weight, MTOW (L)
In this example MTOW (L) - Total Fuel (4000 +800) = 39,200. This is 3,000 lbs more than your MZFW of 36,200 so maximum cargo is:
36,200 -20,000 =16,200 lbs can be carried.
You could carry that left over 3,000 lbs in more fuel if you wanted. Remember though, all weight above MZFW must be because of fuel.
One of the wrong answers on the test will be 19,200. (MTOW (L) – total fuel – empty weight 44000-4800-20000 = 19,200) to see if you grasp that concept. The other wrong answer will be 20,200 lbs. (20,000 + 4,000 +800 =24,800…45,000-24,800=20,200 lbs.) That would be using Crazymax’s example. Correct as it is for small aircraft, it doesn’t work here because of the MZFW.
If, for the sake of argument, your aircraft could carry 15,000 lbs of fuel, you went with full tanks and your Trip fuel was 10,000, then:
40,000 (MLW) + 10,000 (Trip Fuel) = 50,000 lbs. 50000> 45000 MTOW(S) so Landing weight is not a limitation and we can use our full Structural weight. Our landing weight will be 45,000 -10,000 = 35,000 lbs.
45,000 MTOW(S) - 36200 (MZFW) = 8,800 lbs of fuel available to carry a full payload. As we have 15,000 of fuel it is obvious that we are going to have to eat into our available payload to be able to carry that fuel.
45,000-15,000 = 30,000 lbs. 30,000-20,000 (Empty) = 10,000 lbs available payload. Or if you like we “ate” 6,200 lbs of available pay load.
And payload in a commercial operation is just like the name implies, it is the load that pays for the flight. That little tidbit is often lost on people.
So now you have to decide what is more important, getting to your destination non stop in which case you are limited to 10,000 lbs payload
OR
Carrying as much payload as you can in which case you are limited to 8,800 lbs of fuel Max. and stopping to fuel somewhere with the increased costs of added flight time, possible landing fees etc.
Good luck on you exam!
My point is just that it doesn't take a doctorate to figure stuff like that out.TTJJ wrote: Crazymax is correct in his/her assertions, but only as they apply to small aircraft with no MZFW. With bigger aircraft it is a bit more complicated.
(For the newbies, MZFW ,Maximum Zero Fuel Weight, is the maximum an aircraft can weigh with no fuel. Weights above MZFW must be because of fuel.)
Max
