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wangus
26th Aug 2012, 12:42
Scenario.
Single-engine turboprop approach, NDB / DME. MDA of 410' feet. Chart states missed approach point at LCTR. I would fly this as follows. Level out and fly at 410' at just over a mile out and track to LCTR, maintaining 410'. If not visual, go-around at LCTR.
I am being told by an instructor I must initiate Go-around immediately upon reaching MDA, and not continue to MAP on chart, which is at LCTR. (That is what I always did on initial IR...)
Am I missing something?

mad_jock
26th Aug 2012, 12:46
The not so new way of airline ops is to fly a persudo ILS with continuous decent and go around when you get to MDA. FLy the lateral profile of the go-around, so do still continue to the MAPt before changing your heading.

EU ops has banned dive and drive for all commercial operations.

wangus
26th Aug 2012, 12:58
Thanks MAD JOCK. Gulp.... Thank god I asked. Just to reiterate, treat all MDA on NDB approaches as a DH and get the hell out of there???
(Are there publications stating this?)
Do you fly to the Shetland islands etc by any chance?

mad_jock
26th Aug 2012, 13:04
Not really.

EU-ops will have it in somewhere.

It is also normal to turn the MDA into a DH by adding something sensible onto to it depending on the type 30-50 ft for TP's.

Yes I have flown into shetland and the other islands a reasonable amount but not currently.

763 jock
26th Aug 2012, 13:08
A DA has an allowance for sink below the actual DA. Most airlines add 50' to an MDA when flying a pseudo 3 degree path so that the aircraft does not go below the MDA in the event of a go around.

kharmael
26th Aug 2012, 13:26
Of course all this is just a nicety for noise abatement etc. If the weather is rubbish and you need to get in the I'd be inclined to drop to MDA and truck in until I see the lights.

mad_jock
26th Aug 2012, 13:27
767 is correct and sorry for not using the correct term DA as they have done.

Of course all this is just a nicety for noise abatement etc

Its not its due to the high number of aircraft that have had major incidents with coming in completely unstablised approaches by diving and driving.

There is also the issue that in a vast majority of NPA's the MAPt is in a position that it is impossible to get to the runway from.

The more momentum you have the more hairy the approach from close in.

Yes when your flying a 2 ton light aircraft doing 70knts to a 2000m runway its not much of a concern. 10tons plus doing 140knts fully configured it gets ropey as hell.

kharmael
26th Aug 2012, 18:20
Don't have to tell me that, I fly a 70 tonner ;) Maybe all these non-precision approaches hark from a time when pilots were regularly hand flying approaches using the needles and had a better sense of when to go for it and when not to.

I like to think that the MAPt is merely the point where you begin the Missed Approach Procedure rather than the last point where you can get it in, you shouldn't need a MAPt to know that you're probably not going to get it in at say 0.5nm at 600ft ;)

FlyingStone
26th Aug 2012, 19:05
I like to think that the MAPt is merely the point where you begin the Missed Approach Procedure rather than the last point where you can get it in, you shouldn't need a MAPt to know that you're probably not going to get it in at say 0.5nm at 600ft

According to EU OPS, one must start missed approach procedure at DA/DH or MAPt if required visual references aren't acquired - whichever is earlier (in 95% of cases it will be DA/DH), so MAPt lost it's meaning in commercial operations in Europe. The MAPt is positioned so that you can start (initial) missed approach at the MAPt while at OCA and still overfly all the obstacles in the missed approach segment with the required 30 (intermediate) or 50m (final) obstacle clearance.

I agree, it doesn't make a sense to make a go-around at DA in 2 ton MEP or even lighter SEP, if you can increase your chances of getting to runway by flying a level segment to MAPt, but it's a no-no in a larger turbine-powered aircraft, where you'll most likely become unstable (thrust, ROD).

Of course all this is just a nicety for noise abatement etc. If the weather is rubbish and you need to get in the I'd be inclined to drop to MDA and truck in until I see the lights.

Sure, in a light twin, this would be practical, since zero pitch with flaps up will put you in a level flight, adding flaps might even get you negative pitch, which works nice for seeing lights, threshold, etc. I fly a kilo or two lighter aircraft than you and the base reference for flying 3° glide in landing configuration is +2.5° pitch. So how would that work if you'd want to fly level flight in this kind of configuration? Don't tell me you could adequately see runway or approach lights with nose pointing 5, 7 or even more degrees skyward during level flight with landing flaps :)

kharmael
26th Aug 2012, 19:19
I fly a Turboprop, and we (used to) fly NP approaches in the intermediate configuration of 50% flap with the gear down which means you can fly at a neutral deck angle, then you'd take full flap at the last minute, or just land at 50% flap taking into account the extra LDR. Obviously if you're tight on LDA or limiting speeds then you'd have to think about it but then you're into diversion territory ;)

mad_jock
26th Aug 2012, 19:35
If you dive and drive in europe now in a 5700kg plus aircraft on a NPA in a radar enivroment you will very likely be grounded pending investigation whatever your reg.

paco
26th Aug 2012, 20:15
"I agree, it doesn't make a sense to make a go-around at DA in 2 ton MEP or even lighter SEP, if you can increase your chances of getting to runway by flying a level segment to MAPt,"

There are often no performance figures for dragging in for long periods with flaps and gear down....

FlyingStone
26th Aug 2012, 20:59
There are often no performance figures for dragging in for long periods with flaps and gear down....

Having read this couple of times, I still don't get it. What figures would you require? Every half decent aircraft is capable of maintaining level flight in landing configuration (assuming AEO of course), which can be even flaps up (but gear down obviously) for light aircraft, since most instrument approaches tend to lead to quite long runways.

And after all, we're talking level flight in landing configuration from VDP to MAPt - which is maximum 2 or 3 miles, not from London to New York :)

mad_jock
26th Aug 2012, 21:42
Wasn't there a big thing at BHX that used the wrong DME that dragged it in for 10miles at MDA on the NDB onto 33 when the pile of soil meant the ILS was out.

Crew jumped on a company aircraft and legged it and the AAIB got involved and pulled all the boxes.

taxi_driver
27th Aug 2012, 00:11
Air Accidents Investigation: 7/2007 F-OJHI (http://www.aaib.gov.uk/sites/aaib/publications/formal_reports/7_2007_f_ojhi.cfm)

:ugh:

Big Pistons Forever
27th Aug 2012, 01:23
Scenario.
Single-engine turboprop approach, NDB / DME. MDA of 410' feet. Chart states missed approach point at LCTR. I would fly this as follows. Level out and fly at 410' at just over a mile out and track to LCTR, maintaining 410'. If not visual, go-around at LCTR.
I am being told by an instructor I must initiate Go-around immediately upon reaching MDA, and not continue to MAP on chart, which is at LCTR. (That is what I always did on initial IR...)
Am I missing something?

Your instructor is trying to keep you alive, especially if you are single pilot. The killer approaches are those where you get to MDA and can see the ground but not the runway and you are flying half inside half outside slow and close to the ground, the perfect recipe for a CFIT accident especially at night.:ugh:

mad_jock
27th Aug 2012, 06:20
Thanks taxi, it was worse than I remembered.

paco
27th Aug 2012, 07:31
Sorry, didn't make myself clear enough (thinking in shorthand again):

There is the temptation of a dirty dart for the runway if you see it, without really being in a position to cope with the situation—you are in a high drag landing configuration, and likely have been for some time. There are no performance figures for go-arounds under those conditions.

wangus
27th Aug 2012, 08:19
Thanks all.
Given my extreme fear of CFIT will apply all I have read. (Been going through EU OPS unsuccessfully.)

taxi_driver
27th Aug 2012, 11:09
Another one worth reading here:
Air Accidents Investigation: BN2A MK III-2 Trislander, G-FTSE (http://www.aaib.gov.uk/publications/bulletins/october_2011/bn2a_mk_iii_2_trislander__g_ftse.cfm)



‘EU OPS 1.430(d)2. All non-precision approaches shall be flown using the continuous descent final approaches (CDFA) technique unless otherwise approved by the Authority for a particular approach to a particular runway.’