Indigo Call letters for Freshers
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Doubts
The below are some questions from Oxford instrumentation book - objective revision 4 and 5.
Q1) An a/c is descending at a contant mach number. If the a/c is descending through an inversion layer, the RAS will:
a)remain constant
b)increase
c)decrease
d)decrease then decrease more slowly
Answer is b) increase.
however during descent in inversion, temp decreases at lower altitude. so, LSS decreases. since M.no = (TAS / LSS), therefore TAS should also decrease, in order for M.No to remain constant.
Yes, density increases at lower altitudes.
Now, RAS=(1/2)*density*(TAS squared).
Therefore effect of decreasing TAS is more, then increase of density.
so answer should be c) decrease.
Can anyone explain?
Q2)A perfectly frictionless DI, is corrected to give zero drift on the ground at 30 degree north. The DI is set to read 100 degree in an a/c stationary on the ground in latitude 45 degree north. The reading after 45 mins will be:
a) 92.33 degree
b)102.50 degree
c)97.78 degree
d) 103.75 degree
Q3) with constant drift during flight, the a/c heading will:
a)increase by more than 10 degree
b)decrease by less than 10 degree
c)increase by less than 10 degree
d)remain constant
Answer is b). what;s the logic?
Q1) An a/c is descending at a contant mach number. If the a/c is descending through an inversion layer, the RAS will:
a)remain constant
b)increase
c)decrease
d)decrease then decrease more slowly
Answer is b) increase.
however during descent in inversion, temp decreases at lower altitude. so, LSS decreases. since M.no = (TAS / LSS), therefore TAS should also decrease, in order for M.No to remain constant.
Yes, density increases at lower altitudes.
Now, RAS=(1/2)*density*(TAS squared).
Therefore effect of decreasing TAS is more, then increase of density.
so answer should be c) decrease.
Can anyone explain?
Q2)A perfectly frictionless DI, is corrected to give zero drift on the ground at 30 degree north. The DI is set to read 100 degree in an a/c stationary on the ground in latitude 45 degree north. The reading after 45 mins will be:
a) 92.33 degree
b)102.50 degree
c)97.78 degree
d) 103.75 degree
Q3) with constant drift during flight, the a/c heading will:
a)increase by more than 10 degree
b)decrease by less than 10 degree
c)increase by less than 10 degree
d)remain constant
Answer is b). what;s the logic?
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TAS = CAS + DE (density error) and Mach no. = TAS/LSS
Mach no. is constant (given). So TAS is constant.
Now, since the a/c is descending through inversion layer the temp will decrease an so will density error and to keep TAS constant(by d fromula)....CAS will increase!!!
Mach no. is constant (given). So TAS is constant.
Now, since the a/c is descending through inversion layer the temp will decrease an so will density error and to keep TAS constant(by d fromula)....CAS will increase!!!
Join Date: Aug 2011
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I had appeared for the june assessment.....so according to the 3 months cool off period.....when am i applicable again ?
September or October ?
And another question.......Is it mandatory to have ME IR current for appearing in the exam ?
September or October ?
And another question.......Is it mandatory to have ME IR current for appearing in the exam ?
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@hung_start
Quote: Mach no. is constant (given). So TAS is constant.
LSS=38.95*root of temp(in kelvin)
since M.no = TAS / LSS , Therefore LSS changes with decreasing temp. Hence TAS also changes . It can't be constant.
Any one else can explain.
LSS=38.95*root of temp(in kelvin)
since M.no = TAS / LSS , Therefore LSS changes with decreasing temp. Hence TAS also changes . It can't be constant.
Any one else can explain.
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I read that post by LieDetector.......but since there is no such announcement on either Indigo or CAE's website.......m trying to think positive....
Kindly clear my doubts in this matter if you can.....
Kindly clear my doubts in this matter if you can.....
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wings of fire
Q2. Find the real drift due to mechanical imperfections @ 30 N which comes to be 7.5 degree/hour increasing.
total drift=Real Drift + Apparent Drift i.e. 0= RD + 15 sin 30
0= 7.5/hr Increasing + 7.5/hr dec
Now, this gyro is taken to 45N, RD will remain same, no matter what,
Hence, Total Drift= 7.5/hr inc + 15 sin45
= 3.10 degree/hr decreasing
gyro stays here for 45 minutes, so 3.10/hr when computed for 45 minutes comes to be,2.32 Degree/ hour decreasing.
Alteration to the hdg. will be 100-2.32=97.67 degree. (c)
Is the answer correct??
Q2. Find the real drift due to mechanical imperfections @ 30 N which comes to be 7.5 degree/hour increasing.
total drift=Real Drift + Apparent Drift i.e. 0= RD + 15 sin 30
0= 7.5/hr Increasing + 7.5/hr dec
Now, this gyro is taken to 45N, RD will remain same, no matter what,
Hence, Total Drift= 7.5/hr inc + 15 sin45
= 3.10 degree/hr decreasing
gyro stays here for 45 minutes, so 3.10/hr when computed for 45 minutes comes to be,2.32 Degree/ hour decreasing.
Alteration to the hdg. will be 100-2.32=97.67 degree. (c)
Is the answer correct??
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as the temp decrease the local speen of sound reduce
you see the inversion the lss decrease as the a/c descend
Now comes the basic maths , as the denominater decrease to keep the full factor constant (mac no.) we have to increase the TAS and in attampt to increase tas ras increase
ahy update for the indigo coming exam , please inform
Q2, 3 do you have the answer and its justification
you see the inversion the lss decrease as the a/c descend
Now comes the basic maths , as the denominater decrease to keep the full factor constant (mac no.) we have to increase the TAS and in attampt to increase tas ras increase
ahy update for the indigo coming exam , please inform
Q2, 3 do you have the answer and its justification
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Now comes the basic maths , as the denominater decrease to keep the full factor constant (mac no.) we have to increase the TAS and in attampt to increase tas ras increase
now if you reduce 10 to 5 then you also have to reduce 20 to 10, 10/5=2
Now for the answer..cas does increase according to an online flt computer..but dont ask me how..stumped on this one..can anybody explain why cas increases while descending through an inversion layer with constant mach?
And the most basic question..is there going to be an August exam???
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A warm hello to every1 reading this...
Could someone please provide me the solution of the following question:
What is the distance in kilometres from 49° S 180° E/W to 58° S 180º E/W?
Could someone please provide me the solution of the following question:
What is the distance in kilometres from 49° S 180° E/W to 58° S 180º E/W?