Approach Technique

[samdean 0]

The gist of an approach according to the FCOM is something like:

1. Before IAF, set Flaps 5
    
   
2. At "glideslope alive", gear down and Flaps 15
    
   
3. Just prior to glideslope capture, set Flaps 30/40
   

What I find is that by the time I've completed these steps, the runway is generally still a ways out and since I'm slow and fully configured at glideslope capture, it takes some time to reach the runway. It feels like I'm configured too early compared to real-world ops.

 

My question is -- how closely is the above procedure followed in real life? In the spirit of minimizing delays and getting down sooner, I suspect that some of the flap extension (and speed reduction) is done later. I'm sure I've seen a cockpit video when the pilot called for Flaps 5 after glideslope capture. Any real world pilots or SMEs able to chime in?

 

Thanks

Sam Kharey

[Vargveum 53]

It all depends on how far out you intercept the glide slope. 8 miles out, flap 30/40 is "too early". However,vectored in much closer for the intercept, it might be just perfect.

 

I usually go flaps ten on a "typical" g/s intercept. Then drop the gear and flaps 15 around 2000 ft agl. Then the rest follows as we slow to final approach speed.

 

As long as you are stabilised and fully configured at 1000 ft agl in IMC and 500 ft agl in VMC, you're good to go.

[Vagabondo 23]

My question is -- how closely is the above procedure followed in real life? In the spirit of minimizing delays and getting down sooner,

It isn't followed like that because in real life, the aim is not to level off at the platform altitude which the FCTM/QRH procedures assume. In reality, one would try to achieve a constant descent, altering the rate of descent as required to decelerate for flap extension. Normally, this would mean intercepting with Flap 5 at about 160-170 kts around 8 miles. But if intercepting the localiser much beyond 12 miles, one would probably keep the flaps retracted.

 

The benefit of intercepting with flap is that the NG does not otherwise like to slow down. So descending on the glideslope in a clean configuration could actually lead to acceleration. The complication is that flaps should not be used as speedbrakes. So better to use the actual speedbrake to at least maintain the current speed, or landing gear to decelerate. One should try to select flap 1 at about clean speed+10kts with the aim of continuing the deceleration for the next flap extension.

 

On that basis, height and distance are monitored. Normally, I might ask for gear and F15 at around 1500-2000 RA to be configured with F30 and stable at around 1000', if not a bit lower. If the conditions are more challenging then possibly around 2500 RA to ensure stable by 1000'.

[neos63 0]

Hi All

 

When approaching intercept heading FLAPS 5, when inbound FLAPS 15 gear down, arm speedbrake, glide slope capture (ILS) LANDING FLAPS 30/40 "check landing cklist" .

I found this in various landing procedure.

 

Paolo

[Fabo 213]

I find the best procedure to be at 200-210 kts, base, flaps1, slow to 180/F5 to intercept LOC, and dial in 160/F10 on glideslope alive. You should be on 160/F10 when intercepting glideslope, and the airplane will happily hold that.

 

Dial in Vreff+Corr at 4-5nm out, gear down, F15 and then final flaps as speed goes down. I am stable and over idle in 95% cases at 1000AAL, 100% 500AAL.

[cappinsuruje2 1]

I can remember flying on Caribbean Airlines some years ago a short time after they acquired their 737-800s. We were on approach to TTPP and I was sitting on the last row of the aircraft wondering why im seeing the runway and approach lighting. So at this point we were on right base to the runway with no flaps deployed when i noticed the pilot pitch up, deploy speedbrakes, while dumping flaps n gear a short second later. After this we turned right and touched down smoother than any smooth could ever be. I was pleasantly amazed n speechless. Needless to say this has been my approach technique when im in the mood for it..

 

Gidel Warde

[XPX64man 130]

I can remember flying on Caribbean Airlines some years ago a short time after they acquired their 737-800s. We were on approach to TTPP and I was sitting on the last row of the aircraft wondering why im seeing the runway and approach lighting. So at this point we were on right base to the runway with no flaps deployed when i noticed the pilot pitch up, deploy speedbrakes, while dumping flaps n gear a short second later. After this we turned right and touched down smoother than any smooth could ever be. I was pleasantly amazed n speechless. Needless to say this has been my approach technique when im in the mood for it..

 

Gidel Warde

 

That sounds interesting. I'm going to have to try it. B)

[por930 51]

So at this point we were on right base to the runway with no flaps deployed when i noticed the pilot pitch up, deploy speedbrakes, while dumping flaps n gear a short second later. After this we turned right and touched down smoother than any smooth could ever be.

This is how we used to land on bush strips, work out where the wind direction is, then sort of swoop in and get down, otherwise, the hot air currents get to you as you make a "usual approach", and throw you all over the place. Might add though, using my trusty old Cessna 182 is a tad different to the 737.