Announcement

Collapse
No announcement yet.

2736

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • 2736

    Hi,

    A monkey could probably work this out, but im no monkey.

    The question asks for the landing moment.

    The TO moment is 432226

    The block fuel is 100usg, trip fuel is 55usg with taxi fuel being 3 usg at a density of 6lbs per gallon.

    At landing then, the only weight we would have lost would be the trip fuel.

    100-55=45usg (taxi fuel not being included in the TO moment?)

    45 x 6 = 270 270 x 93.6 (BA) =25272

    432226-25272 = 406954, which is close, but still 5616 out.

    5460,

    I?m stuck on this one too.

    Not sure where to start. Have worked out the CG to be at 3.5m but adding two different loads at 2 different locations, I?m not sure how to make the formula fit. Very frustrated having spent hours on M&B today never to break the 77% mark.

    I have one more and then its time for some relaxing HPL

    3575,

    Determine the landing mass. Piece of cake right?

    1764+35+300+350+150(60-35=25x6) = 2599,

    But the answer is 2589, I know its going to be bad when someone shows me where the extra 10 came from

    And well, there are many others but I feel I?m hogging the forum.

    Many thanks,

    Conner1
    Last edited by Conner1; 13-01-2005, 23:13.

  • #2
    Q2736 At reference or see Loading Manual MEP1 Figure 3.4.
    With respect to a multi-engine piston powered aeroplane, determine the total moment (lbs.In) at landing in the following conditions:

    Basic empty mass: 3 210 lbs.
    One pilot: 160 lbs.
    Front seat passenger : 200 lbs.
    Centre seat passengers: 290 lbs. (total)
    One passenger rear seat: 110 lbs.
    Baggage in zone 1: 100 lbs.
    Baggage in zone 4: 50 lbs.
    Block fuel: 100 US Gal.
    Trip fuel: 55 US Gal.
    Fuel for start up and taxi (included in block fuel): 3 US Gal.
    Fuel density: 6 lbs./US Gal.
    Total moment at take-off: 432226 lbs.In

    Solution: The total moment at landing would be the total moment at take-off less the moment of fuel used. The fuel used depends on what is meant by trip fuel, is it T/O to touchdown or engine start to engine stop?

    If the former, the trip fuel is 52 USG or 52 x 6 = 312lb. The balance arm is 93.6 so the moment change is 312 x 93.6 = 29203, the new moment is 432226 - 29203 = 403022.

    If the latter, the trip fuel is 55 USG or 55 x 6 = 330lb, the moment change is 30888 and the new moment is 432226 - 30888 = 401338. This is the only answer that matches so this must be what they mean.

    Q 5460 The mass and balance information gives :

    Basic mass : 1 200 kg ; Basic balance arm : 3.00 m

    Under these conditions the Basic centre of gravity is at 25% of the mean aerodynamic chord (MAC). The length of MAC is 2m.

    In the mass and balance section of the flight manual the following information is given :

    Position Arm
    front seats : 2.5 m
    rear seats : 3.5 m
    rear hold : 4.5 m
    fuel tanks : 3.0 m

    The pilot and one passenger embark; each weighs 80 kg. Fuel tanks contain 140 litres of petrol with a density of 0.714. The rear seats are not occupied.Taxi fuel is negligible.

    The position of the centre of gravity at take-off (as % MAC) is :

    Solution: The CG position at take off can be found by dividing the total moment by the total mass. Total mass = 1200 + 160 + 100 = 1460kg.
    Total moment = (1200 x 3) + (160 x 2.5) + (100 x 3) = 4300kgm, the CG is therefore at 4300 ? 1460 = 2.945m, a forward movement of 3.00 - 2.945 = 0.055 m or 5.5 cm from the BEM position.

    We know from the question the MAC is 2m long so 0.055m is (0.055 ? 2) x 100 percent of the MAC, or 2.7%.

    We were at 25%MAC, we are now 2.7% forward, the current CG is 22.6%MAC.

    Q 3575 Determine the Landing Mass for the following single engine aeroplane.
    Given:

    Standard Empty Mass :1764 lbs
    Optional Equipment : 35 lbs
    Pilot + Front seat passenger : 300 lbs
    Cargo Mass : 350 lbs
    Ramp Fuel = Block Fuel : 60 Gal.
    Trip Fuel : 35 Gal.
    Fuel density : 6 lbs/Gal.

    Solution: 1764 + 35 + 300 + 350 + (25 x 6) = 2599. Lord knows where the extra 10 came from!

    Comment


    • #3
      Alex,

      Thank you very much for taking the time to write out such full explanations to all my questions.

      I can see clearly that I am a jack of all trades and as yet a master of none, well maybe comms.

      Thanks again Alex,

      Looking forward to Monday

      Kind regards,

      Conner1

      Comment


      • #4
        Re: 2736

        With this question, the pop-up with the table refuses to show up.
        I get an empty window with an error "page not found"

        Etienne

        Comment


        • #5
          Re: 2736

          Hi,

          As for the "extra 10", I've seen this question in another question bank and comparing it with this the question misses a line where it mentions that 10 lbs of fuel are consume during taxi, hence that should be deduced from the landing mass too.

          Cheers.

          Comment


          • #6
            q3575

            What does the question mean by 'optional equipment'?

            If its optional does that mean we could calculate the landing mass with 35lbs less mass if we decide not to take the optional equipment? (2554 lbs) ?

            I'm thinking optional equipment might have got lost in translation....

            Comment


            • #7
              Re: 2736

              When I asked the CAA about this a year ago they agreed that "optional equipment" could be part of the BEM/DOM and they took it out of the question. However seats have changed in the crystal place and its back in! What can I say, clearly its used as part of the solution.

              MOHIT: thanks for the info on the 10lbs taxi fuel-I'll get it put in the question.

              Colin

              Comment


              • #8
                Re: 2736

                Just to confirm that its back, the 'optional equipment' turned up in today's exam.

                Comment


                • #9
                  just stuck on this question!!
                  İs there anyone her who can help me?

                  Comment

                  Working...
                  X