>>>five digit number becomes complicated and confusing by
>>>the addition of one more digit...which is always either a 5 or a 0?!


All I can say is that you have never flown into LHR or LGW at peak hours. What is easier to recall, 132.475 or 3247?

And the proof of the pudding is the number of missed frequency changes, especially while in 'foreign' regions. I count about six or ten missed frequencies every day. Thats six or ten opportunities for extra ATC stress and a potential incident. And for what reason? Because some desk-jockey has only half a brain and did not ask users what they want.

Besides, when you are on a very busy frequency, with no room to get a word in edgeways, what is simpler and shorter to say - 132decimal475 or 3247 ?? So ATC are struggling to control the numbers of aircraft in thier sector, because of unwieldy phraseology. KISS wins every time, while complexity leads to incidents and accidents.

I've just timed myself saying both of your examples. 1.0 second for the long one. 0.8 seconds for the short one.

Not exactly a life saving difference.

Both are just as easy to recall, for me anyway, having just heard them.

Funny you should mention those airports. I've been based at both, at separate times, for a total of 15 years.

Nothing to do with GPS, however i suggest you check FCTM page 5.39 (Raw Data Monitoring Requirements). Raw data monitoring is recommended but not required both for classics (EFIS update 7.2 and FMC version > 7.1) and NGs. The MEL allows dispatch with the ADF inop as long as one FMC is operative even for NDB approaches.

Sorry, but you cannot do an ADF approach without an operating NDB and ADF - period !

If you do not have a ground station and the appropriate cockpit instrument, you are doing an RNAV FMC approach, not an ADF approach. And we have no RNAV approach plates in our Euro-Jepps, and so I'm presuming that RNAV (FMC/GPS) approaches are not yet certified to any of the airfields we visit.

Your reference in the 737 FCTM is referring to whether "raw data" or "map display" is selected - not whether the ADF is working or not. In other words, you can use map display mode, if you have overlaid VOR or ADF pointers for cross-checking (which many systems can do) or you flip between raw data and map display to check that the map is in the right position.

Note the note at the bottom of this section: - "Compare VOR and ADF systems to detect possible map shifts". You cannot do a map cross-check, if the VOR or ADF is u/s or not fitted !!


This is what happens, when people use a (map-shifted) RNAV FMC approach, instead of the raw NDB/ADF.
1996 Croatia USAF CT-43 crash - Wikipedia, the free encyclopedia


Ditto the B-Med Airbus going into Addis Abeba. The FMC plot and terrain display were off by some 3 miles, leading to a go-around just 60 ft over the high terrain. Now while the VOR would give occasional signals of its unreliability (the VOR was the primary fault), the FMC gave no indication that it had a map-shift. This was the biggest complaint in the report, that the FMC knew it was getting bum VOR information, and therefore may have a map-shift, but did not bother to tell the pilots. And the pilots could not check for a map-shift, because they were comparing bum data with bum data.
Report: British Mediterranean A320 at Addis Abeba on Mar 31st 2003, wet VOR nearly causes two CFITs

Incidentally, the New Scientist report on this indicated the crew were highly influenced by the terrain display, which showed them passing nicely through the valley. However, the terrain display was likewise mapshifted. Not sure where this info came from, because the AAIB report underplays this aspect (that the crew were merely following the FMC and terrain plot, and disregarding the raw VOR signal).

One would have thought that following an erroneous and displaced VOR radial would bring you eventually to the VOR, whereas this flight paralleled the VOR inbound, which is what would happen if you followed an erroneous FMC position.

Search Results - page 1 - New Scientist



And I am not even sure that GPS-RNAV is entirely a solution at present (as was recommended in the B-Med report). It works well with high accuracy and reliability, but Europe is still concerned that the US may degrade GPS signals or switch the system off during periods of international tension. This is the primary reason for Europe developing and launching the Galileo GPS system. When that is up and running, and there is full confidence that erroneous signals can be detected and warnings given, then Europe may proceed to RNAV approaches.

Slight exaggeration maybe?

Operation of the rudder trim does not give full rudder deflection. The two accidents you mentioned were thought to have been caused by full un-commanded deflection of the rudder but in the reverse sense to the movement of the rudder pedals. Very few pilots could have recovered successfully in the limited time at their disposal in both those events.

But even with full rudder trim deflection applied inadvertently, the 737 in the ANA incident would never have got to the extreme attitude that happened without some crazy manual flying inputs by the pilot.

have i missed something?
 

i've read as many of the replies as i could and though i have seen it implied, would i be out of line to say in simple terms, this was the work of a complete idiot, jobsworth, waste of space pilot?

yes, we have all touched the wrong switch and have pushed the wrong button but if we are simply paying attention to the present situation, we see the wrong result and make a correction right away. but to hold any knob, switch, handle regardless of the shape for such a length of time and not notice the aircraft beginning to roll over is the work of a total idiot.

can't blame the airplane for this one!

I think you negate the role of the autopilot.

During the two left rudder-trim inputs, the autopilot will have been counteracting with aileron - hence the slight opposite right roll to start with. Then the autopilot will go out of limits and disconnect, and so the resulting uncorrected roll rate to the left may well be quite dramatic.

Exactly as SS says - I know of one previous incident caused by mis-management of fuel balancing where the bank angle exceeded 90 degrees on A/P disconnect.

New captain at big airways and he was over the alps at the time iirc!

Because he thought that this is the door knob: suspected train of thought: "Ah captain wants back in. Lets open the door - uh oh, something is wrong - why is the captain not coming, help! Lets kick the button a bit more so he finally gets into the cockpit - uh oh, its getting worse - c'mone door, open.. (Keeps on turbning the button frantically..."

You can't be serious.

Well, maybe you are...I recall some of your previous posts.

I can understand what has happened, the FO would have activated the rudder trim and would have then been distracted by looking at the aircraft deviating away from normal. That initial confusion was no doubt replaced by panic when the aircraft had a serious 'upset'. It would have been when action was taken to recover the aircraft that he actually 'released' the trim. No doubt had was frozen on there whilst brain tried to process what the hell was going on. I think some recognition could be given to him for actually recovering the aircraft back to 'normal' with out further 'upset'. We have already seen several times in recent history that in these situations a bit of mishandling in 'upset' situations can lead to the loss of the aircraft. Yes he co*ked up getting into the situation but thank god had enough basic handling skills to recover from it. These basic skills are what seems to be lacking in certain areas.

Think again. He already has caused a major upset (unusual attitude) by putting the aircraft into an almost inverted nose down situation of his own making. . And does this therefore prove he had enough basic handling skills in the first place? I don't believe that for one minute. He then eventually gets the aircraft right way up. I would say that was the result of pure bloody good luck - not good basic handling skills. The facts will eventually be published although maybe kept in-house. The guy has a pilots licence but that's about all.

Found the following on a website blog. Does the 737-700 AP have a CWS function?
Re the ANA 737-700 incident. There is not much to go on because only media reports are available at present. So who did what to which is unclear. Maybe when the F/O hit the wrong switch (he got the rudder trim rotary knob) the door didn't click open or whatever the door is supposed to do to unlock. Someone mentioned earlier it takes 29 seconds for the rudder trim to move from centre to full scale left or right.

The ANA incident happened at night. This is significant as we shall see. Assume the F/O held on full rudder trim maybe not for 29 seconds but a significant amount of time. Eventually the autopilot either went into CWS roll as the control wheel turned to maintain the present heading - or the autopilot disconnected altogether causing the aircraft to roll. It maybe the first officer then lost control when he tried to hand fly at high altitude at night in IMC on instruments. Most of his 737 flying would have been on full automatics from shortly after lift- off to shortly before touch-down.

Another possibility is if the CWS roll did remain in place (in other words it had not yet disengaged itself) and the unusual position of the control wheel alerted the F/O to something going wrong. If he then tried to correct to wings level too harshly with CWS roll engaged it may have caused the autopilot to disconnect in the roll mode and pilot confusion with hand flying (lack of instrument flying skills) could eventually lead to an upset.

Or if the F/O inadvertently hit the stab trim switch on his control column at any stage while the AP was engaged in any mode, the AP will disengage in all axis leaving the F/O to hand fly and he probably did not have the ability to do so. It may have been a different story in day VMC but to have a typical F/O steeped to use automatics throughout his career on the 737, then a IMC recovery is going to be a real problem.

Am I missing something ?

Some FDR traces are available on the PDF by the japan agency.
The duration of the rudder trim inputs are shown on those traces.

Why do people still elaborate theories about "29 seconds, what a fool to keep that for so long", when the traces show 2 inputs, each one with a duration of ~5-7"

29 seconds is the time it takes to go from trim neutral to full trim. Nowhere was it said that in ANA's story the knob was held for 29 seconds!!

Thread drift,

Lord SM, if you've done some human factors in terms of short term memory you should know that the magic number is 7.

One, two, three, decimal two, seven, five uses it all and doesn't leave space for heading, speed and/or altitude changes to be included.

Also the fact you've done 15 yrs around London doesn't mean everyone has, some of us fly in Europe less than once a month.

The brain also uses chunking in short term memory such as twos (1,2) threes (3,4,5) and fours (5,6,7,8).

132.475, two chunks 3247 one, leaving more short term memory for HDG / SPD & ALT in the same instruction.

Now lets talk about fatigue ...............

On a point of pedantry, one doesn't pronounce the 3rd decimal place. Thus, your frequency should be pronounced "One, two, three, decimal two seven" (leaving apart, that it, the pronunciation of "tree, fife" etc :)

Of course not, but pilots just love to talk out of body cavities that weren't meant to talk out of

@Pontius: check your knowledge of the relevant R/T procedures:

No answer, Denti, about this novel idea of doing ADF approaches without an ADF?? !!

I presume you are a training captain with a well-known low standards airline. They were mostly crap instructors.

.