[A320] Correct time for FLAP 1
 

Dear Colleagues,

As a general rule it is suggested 3NM before FDP to select FLAP 1. (conditions permitting) However on some straight in approaches you may be cleared for the approach from a high altitude and more than 25NM from the field. In this scenario, you will be intercepting the LOC and GS well before FDP.

In such situations it is advised to activate the approach phase 15NM from the field but when is the correct time for FLAP 1as there is no longer a requirement to be at platform altitude to intercept the GS from below? What I would expect is we would select FLAP 1 prior to GS capture but that would be too early from about 10-15NM resulting in us dragging it in. However I do not want to be on the GS without at least FLAP 1 as per FCOM.

Thanks in advance!

So it really depends…

if you’re not doing a straight in as a general rule you want flap 1 on base leg (no later then when on an intercept heading for the LOC) ATC should inform you of this with language like “…on this heading you are cleared for the approach”

if flying straight in remember you can always activate the approach early and maintain your speed in selected mode until you want to decelerate towards green dot.

if doing a decelerated style of approach you’ll want flaps 1 and S speed out at least 2-3 miles before FDP otherwise achieving Flaps 2 will be tough without speed brake/gear once on the GS.

it’s quite rare to be cleared for an approach as far as 25nm and in most cases ATC will clear you for the approach and clear you down to the platform altitude at the same time so in this case simply keeping slightly below the GS (ie 1 dot) simply by using VS having armed the approach should allow you to manger the energy until closer to the FDP.

communicating with ATC for further descent even after cleared for the approach way out at an altitude higher then platform may help your situation so long as you respect the MSA/terrain etc.

so to answer your question, it’s imperative to have flap 1 min out and S speed before GS capture. And off all else fails you always have the gear! 😆 nothing will slow you down better then those bad boys. Bit noisy though out at 15nm

i hope that helps.

There's your answer.

As ever, have a look at the wind. Any hint of a TW on base or final, get slowed down early. Often happens at night where surface winds are calm.

This applies when STARs/Approach permit. Aka no mandatory speeds, etc:

My personal technique is when inside 30 NM radius of airport, I "start thinking about" Flaps 1 and slowing down. 30 NM I will roll speed back from 250 to 220 or 210. I am for sure Flaps-1 and 210-ish or maybe 215 on downwind. If I am 210 on the speed, I am almost always putting flaps 1 out, to help with VLS and speedbrake usage. Base leg, 180 and Flaps 2. Turning final, 170 and flaps 3 to 4 and gear will be dependent on where I am on the approach. Outside of the FAF, I am typically pushing speed to managed and further configuring.

IMC or VMC, I personally seek to be fully configured, all checklists done, at 1500 feet, and absolutely by 1000 feet.

May seem like grandpa flying but this keeps me ahead of the plane and keeps the blood pressure and excitement down.

*** again, STAR/Approach dependent and local ATC (NY Airspace, etc) dependent. This is my general technique

If I am in a heavy 321 I am more OCD about slowing down.

If you’re on a very long final, the plane will maintain the glide slope just fine with flaps up. Airports like ORD and LAX quite often have you join at 30ish miles out.

When you anticipate that you will not have another opportunity to slow down enough to get the flap out.

Any copyrights on that? Love it.

Feel free.

@Aerocat
I don’t understand. Maybe I don’t get you right, but
There are more opportunities to slow down, e.g.
what’s about speedbrakes
what’s about gear

If cleared for ILS far out and high you can follow the GS in clean at GD and just before platform altitude take speed brake and gear down to get below VFEnext put speed brake in and configure all the way. It's non standard way.

This forum needs a like button.

Those are tools not opportunities. Indiscriminate use would be poor flying.

Being ahead of the airplane, you keep evaluating what happens next. Take flaps out at the last good opportunity that warrants a stable approach without the use of increased drag techniques.

Cheers all some great advice! - Will take it on-board and hopefully get a chance to apply it. Thanks once again.

My plan is to configure in the standard sequence without use of the speed brakes. That leaves speed brakes and gear available as an option if I cock it up. If my plan was to use speed brakes and gear from the outset then I’m not leaving myself anything else to fall back on when I invariably cock it up.