ATPL theory questions

[Alex Whittingham]

If you don't want to pay, the one known as paco has one that I think is free. He'll be on shortly I imagine. Most pay-for-use QBs give you free access for a limited time.

[paco]

The one known as paco is indeed lurking....

rtfq.org

No explanations, 50/50 button. use like flash cards

[Specaircrew]

Detrol5

If you can stretch your budget to £12 you could give atplontrack a try for a month ;-)

[Central Scrutinizer]

Originally Posted by Marnixsjoerd

Hi,

Does anyone know if EASA uses 27 or 30 hPa for calculations?
I've come up short in my google search as they are both mentioned.

Thanks for the info

This is an interesting question.

When I sat my exams 2017-18, some subjects used 27 ft/hPa and others used 30. In fact, I remember a question in which depending on which assumption you used you obtained one of the possible options or another, which is really just plain mean by EASA.

[paco]

I believe the standard is now 30 (for the new syllabus), but the question should specify

[ATPLeasa]

Good day pilots,

Currently studying for atpl exams and I stumbled upon a weird question in performance. "Most jet aircraft cruise at ___ of their maximum rpm"

I have studied both ATPL questions and now aviation exam and it appears the answer is different in each database.

In aviation exam it is: 75-85%
while in aptl questions the correct answer is 85-90%

So which one is correct? or most correct?

[Specaircrew]

All the multi engine jets that I've flown are definitely in the 85-90% RPM band with the possible exception of the Vulcan which was so overpowered that long range cruise power, as I recall, was slightly less ;-) Of course the person that set the question may live in the theoretical rather than the real world, however my ' Boys Book of Aeroplanes'(AP3456) states that turbojet aircraft cruise using approx 90% of max thrust for the best range.

[Banana Joe]

Jet engines are more efficient at high altitude and high rpm because of better SFC.

[john_tullamarine]

When I sat my exams 2017-18, some subjects used 27 ft/hPa and others used 30.

Just so long as we all keep in mind that both are wrong except for the particular Hp values where they are correct (around 3000 ft).

For interest, I put some stuff which you might find relevant at the following link

Bob Tait's Aviation Theory School - DenAlt... 1 Degree C = 120 feet and also = 500 feet. WTF? - Bob Tait's Aviation Theory School Forums

which includes a link to another thread which has a graphic which may be useful

Bob Tait's Aviation Theory School - Altimetry Rates - Bob Tait's Aviation Theory School Forums

Some of the fanatical support for 30 ft/hPa I see around the traps beggars belief ...

[ashdaviator]

Mass and balance

A twin engine aeroplane is certified for a MSTOM and a MSLM of 58 000 kg and
55 000 kg respectfully. What is the limiting take-off mass for the aeroplane?
PLTOM 61 000 kg
PLLM 54 000 kg
MZFM 36 000 kg
Operating mass 55 000 kg
Trip fuel 36 000 kg
Alternative fuel 500 kg
Final reserve 500 kg
Flight duration 3 hours
Fuel consumption 500 kg per hour
OR

What is the maximum take-off mass given:
MSTOM 43 000 kg
MSLM 35 000 kg
PLLM 33 000 kg
MZFM 31 000 kg
DOM 19 000 kg
Total Fuel capacity 12 500 kg
Maximum Trip Fuel 9000 kg
Contingency fuel 1000 kg
Alternate fuel 500 kg


Unable to figure out a clear methodology to solve these questions, unless solution is seen. Do i need a basic table reconstruct and how should it be ?

[flapsupboy]

use this to understand the basic principle

This will help you for a lot of questions.

[ashdaviator]

Already using this. but may be need more practice with this to get correct flow in solutions. Thanks a ton for sharing

[tacvbo]

GNAV question

Hi guys,

I'm sitting over this question and cannot find my mistake. Maybe I can't see the forest through the trees.

Given: TAS 120kt
ATA at A: 12:32 UTC
ETA at B: 12:47 UTC

ATA at C: 12:50 UTC
ETA at D: ?

(Distance A to B = 30 NM; Distance C to D = 20NM)

One could say, easy: 20NM/120kt = 10', ETA at D is 13:00 UTC but this answer is marked wrong.

I was thinking that at B it's only an estimate, so I figured maybe we're flying slower or faster.
Actual time at A 12:32, actual at C 12:50, flight time of 18'.
distance: 30NM + x
V: 120 +- y

When I use the TAS of 120NM, the distance between B and C is 6NM and t=0,05 (3') and everything checks out. But the answer of 13:00 UTC is still wrong.
I'm grateful for any hint.

[hvogt]

You cannot tell an ETA from TAS. You need to find the GS first. Perhaps, it might help if you posted the complete question with all the suggested answers.

[mechpowi]

Originally Posted by ashdaviator

A twin engine aeroplane is certified for a MSTOM and a MSLM of 58 000 kg and
55 000 kg respectfully. What is the limiting take-off mass for the aeroplane?
PLTOM 61 000 kg
PLLM 54 000 kg
MZFM 36 000 kg
Operating mass 55 000 kg
Trip fuel 36 000 kg
Alternative fuel 500 kg
Final reserve 500 kg
Flight duration 3 hours
Fuel consumption 500 kg per hour

​​​​​​The Trip Fuel can't be 36 000 kg if it's 3 hours at 500kg/h!

[tacvbo]

I assumed TAS = GS because no wind was given.
The answers were: a) 1303 UTC b) 1302 UTC c) 1257 UTC, d) 1300 UTC

[Kylethomo]

Great thread

Loving it guys!

[Hawkers]

Hi.

We have started a series of free lessons and explanations with videos about "problem topics" for ATPL students.

The first one is about chart convergency. https://www.easy-pilot.com/blog/what...rt-convergency

If there is any topic you need help with just reply on this comment with the name of the "problem topic" and we will try to help.

[flywith_neil]

Originally Posted by Hawkers

Hi.

We have started a series of free lessons and explanations with videos about "problem topics" for ATPL students.

The first one is about chart convergency.

If there is any topic you need help with just reply on this comment with the name of the "problem topic" and we will try to help.

Thanks, that is actually pretty straight forward. Any chance you can do one on fuel planning? Point of equal time, safe return, and the reduced contingency?

[paco]

"Chart convergency refers to the phenomenon where meridians (lines of longitude) converge towards the poles on a Mercator projection aeronautical chart. "

Your first problem is that the meridians do not converge on a Mercator chart...... they are parallel. Shirley you mean Lambert?