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Old 1st Jun 2004, 16:18
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Autothrottle

Can anyone help me with these questions? Cause I'm stuck.

The autothrottle system at touchdown will
a) Apply reverse thrust
b) Go to idle
c) Go to idle and disconnect


When will the decision height aural warning sound
a) At decision height
b) Before decision height
c) After decision height


A category 3B aircraft using fail operational automatic landing equipment will have
a) A decision height of 50ft
b) No decision height
c) Decision height will depend on RVR

Thanks in advance
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Old 1st Jun 2004, 16:48
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CAA questions i take it?

Autothrottle goes to idle at the flare retard command from the Autopilot and thats hopefully before touchdown!! The 747 A/t only dissconnects with reverser application or if the pilot dissconnects it.

At the decision height.


Cat 3B is no decision height. this is the max autoland available at most airports, 3C requires taxi guidance to the gate.

Hope this helps.

Stu.
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Old 1st Jun 2004, 21:05
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Cat 3b can have a decision height below 50'
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Old 1st Jun 2004, 21:07
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True it can , but that would be the pilots chioce, 3B allows for full autoland down to the ground in the orst of weather. Is the max we have at the moment.
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Old 2nd Jun 2004, 03:16
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Might help if we knew which aircraft they were talking about

A 737NG will put the throttles to idle during flare (prior to touchdown) and the A/T will disconnect 2 seconds after touchdown.

Rgds.
NSEU
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Old 2nd Jun 2004, 08:28
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Question 1. Answer depends on a/c type! Looks as if the examiner has a particular a/c model in mind!
Incidentally, no answer is correct for the A319/320/321 as the pilot has to select idle thrust.

Question 3. No completely correct answers here, either!
B is "more" co rrect, but many states don't allow "no decision height" Cat 3B operations.

It appears that the person who set these questions is not "au fait" with AWOPS

Preppy.
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Old 2nd Jun 2004, 14:15
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Hi

You guys are right but thease questions sound like CAA Eng licence q's and there all like this unfortunaltly. Type specifics cannot be brought into it, which makes the definitive answer hard to find! e.g the post that mentions the airbus pilot selecting idle, true, but this has no bearing on the question as an airbus has no auto throttle, its auto thrust. see what i mean about type questions getting messy! You have to think "CAA" autothrottle.

As for the 3B, iam a licenced avionic eng and were taught that 3B is no decision hight, thats the capability, what AWOPS says is not important for the question. Thats an operational concern.

Cheers,

Stu.
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Old 2nd Jun 2004, 17:06
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if the questions are for the JAA ATPL exams than the answer for question number 1 should positively be ´to idle and disconnect´as NSEU pointed out. since the 737-400 is the JAR25 aircraft of reference for the examination. this might also hold true for the eng. exams. not sure.
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Old 2nd Jun 2004, 19:18
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The questions are yet again an example of the poor standards within the examination process. The examiners make far too many assumptions and they exhibit their own poor knowledge of aircraft systems and flight operations. Questions of this kind do little to test the student and in general reduce their self-confidence about aircraft knowledge and operations in general. In addition, the examiners add confusion by sowing seeds of doubt at an early stage of a career:- first learnt, best remembered.

An answer to question 1 (b) should be qualified by the aircraft type i.e. Avro RJ Thrust levers “retarded” to ground idle.

For question 2 – where there may be no appropriate answer, add the aircraft type and the operation. i.e. Avro RJ, “my airline”; the ‘minimums’ call sounds at the bugged radio altitude, but my airline’s SOP (CAA approved) is to set the radio altitude DH bug to DH plus 15 ft.

Question 3 is a mess as it mixes aircraft certification standards with flight operations.
For certification of the aircraft, the requirement for fail operational landing system is defined in JAR-AWO, “a Cat 3 operation with no DH or DH below 15m”; definitely not student reading matter.

Cat 3B is an operational clearance, that a) requires a suitably equipped aircraft (JAR-AWO); and b) approval from both the national authority of the operator and the authority of the airfield where the operation is conducted (outside JAA).

JAR-OPS complicates matters further as in table 7 of Subpart E appx 1, DH is listed against RVR (three RVR options for Cat IIIB), and furthermore the only reference to fail operational equipment is that for rollout guidance.
The text in subpart E fails to clarify the ambiguity, whilst subpara 4 (ii) states the equipment required, the value of DH is not explicit.
Subpara 4 (iii) deals with no DH ops but without reference to the required equipment.

Thus question (c) can only be answered with caveats, but what chance that a student will have (or indeed requires) the necessary information or experience.
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Old 3rd Jun 2004, 17:50
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Thanks everyone. Yes they are CAA questions. I have got my exam a week tomorrow. I'll just have to hope I don't get these questions.

Our CAA Engineering licencing body are in a complete mess at the moment. Would you believe I sent them a registered letter 4 weeks ago, asking what syllabus I would be examined on and they have not replied ? Trying to phone them is a complete waste of a day and they don`t reply to emails.

God help us.
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