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ollicrj
14th Mar 2010, 17:44
Hi!
If there is a go around procedure requiring to maintain altitude (MDA = GA ALT),
will the A320 stay in level flight after selecting TOGA thrust and thereafter reduction to the climb detend again?
You have to select TOGA momentarily to activate the GA routing, and normally the modes thereafter are TOGA SRS GA TRACK. But what about this case? Thanks for clarification...

gusting_45
14th Mar 2010, 20:46
Push V/S to maintain altitude. Select speed to facilitate clean up. DIR TO an appropriate waypoint on the MCDU. Job done.

TopBunk
14th Mar 2010, 20:46
Are you suggesting that in a G/A case you must maintain MDA? Let's say 400 ft agl?

If so, can you give us an example of where this exists as a G/A procedure. If you can't then it is a pointless question.

If I have misunderstood, then I think you need to clarify your question.

mcdhu
14th Mar 2010, 23:05
If my memory serves me correctly (because I haven't been there for a while) the NIZ 'Riviera' VOR/DME 04L/R circling with prescribed tracks approach requires the procedure described by Gusting_45 above.

If there is an ILS involved, press the App Pb as soon as you can. The Airbus has been known to snap violently upwards to capture false G/s lobes.

Our 'Discontinued Approach Procedure' goes like this:

VS Push
Select Green Dot
If GS Armed, Push App Pb
Flap In 1 Stage (if appropriate)
Gear Up (if appropriate)
Use V/S and FCU Alt to achieve desired Alt
Further Flap Retraction on schedule (if appropriate)

Hope that helps. It is really designed when you are sent around from an Alt above the FCU alt in which case, if you engage TOGA, SRS will take you skywards until you intervene.

CAT3C AUTOLAND
14th Mar 2010, 23:52
I have never seen a missed approach procedure, where you have to maintain a DA/DH or MDA?

Are you referring to the high level go around? If so there are 2 ways of doing it.

As has been mentioned, you can simply select TOGA, which will activate the GA mode then pop the thrust levers quickly back into the CLB detent. The only problem with this is it is easy to bust the GA altitude if you are close to it in the first place, and possibly exceed VFE. The procedure we use in the ailrine I fly for, is to push VS, which will maintain your current altitude and call go around flap (retract one stage). Once you have established level flight raise the gear, and use VS to climb or desend to you GA altitude, then using selected speed to accelerate and clean up. You can also pull for heading to disengage LOC mode, then push for NAV to fly the lateral profile of the GA procdure.

FatFlyer
15th Mar 2010, 19:18
Hi,
as the chap above said, the Nice riviera approach has an MDA of 2000 ft which is also the initial stop altitude for the go around. Thrust levers put to TOGA would obviously bust this. Most operators have some type of discontinued approach procedure as described above where TOGA thrust would be inappropriate.

320 driver
22nd Mar 2010, 00:36
Topbunk

I think your description of the question as pointless is rude and marks you out as somewhat ignorant.

A great many circling approaches have MDA=MApp stop alt.

Hitting TOGA whilst in ALT or VS0 will engage SRS if you are not clean and cause a rapid climb. Procedure described above will work. However, if you are on an A/C with FMS1 standard it may be an idea to temporarily select a TO WPT some distance away as the FMGC will enter DONE mode as you pass over the airfield and dump your beautifully crafted F-PLN.