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Stabilized approach? How would you do this

Emir wrote:

Dave_Phillips wrote:
……. Decision Altitude at up to 200kts and take things from there. At times, I will keep 200kts to threshold, especially if I’m aiming for a fast exit some 7000ft down the runway.
200 kts IAS?

Yes, the aircraft will handle it. (PA31/DA62).

OK, that’s an extreme, but I think that many of us in GA get a little too focussed on ideal speeds etc. In the calibration world, I will setup a ‘profile’ where the aim is to follow the relevant ILS signals from 12nm/3500ft to the upwind threshold. The last mile or so is flown in level flight along the runway at 12-50ft AGL. ALL of that is done at a constant power setting of about 47-50%. So, top-of-drop is about 105-110KIAS and the level-off near the approach PAPIs is at about 200KIAS. The far end of the runway normally arrives at about 110KIAS. The whole profile is flown clean but I can guarantee a safe landing at any point up to 3000ft from the runway end. After that, it’s a go-around.

My point? Many/most light GA aircraft are extremely flexible and capable of dealing with things that a heavier aircraft cannot handle. Let’s not get hung-up on stabilised approaches; we don’t necessarily need to do them.

PS. Our weather minima for the above profile are 1200m/350ft and we are following a computer generated equivalent of an ILS HSI.

Fly safely
Various UK. Operate throughout Europe and Middle East, United Kingdom

Cobalt wrote:

In IMC, however, this is a different story.

I would agree that it should be practiced and polished in VMC, but once you have done it a few times in VMC, it really is not an issue in IMC.

Of course, I am assuming that you are doing it at Gatwick or Cologne and not Malaga. In which case being a couple of dots below the slope at 4nm is no problem at all. You get extra speed of you start a couple of dots above the slope, and descend through it to keep speed up while reducing power.

You can then gently pull through the slope to two dots above which, in everything I have done it in, brings the speed to flap-limiting first, which helps slow down more, then gear limiting quite quickly. As soon as the gear is down, you hold Vle while continuing to reduce power and very soon you are back on the slope. The whole exercise is complete by about 3nm, so 950’, and is really quite unthreatening, even in IMC.

EGKB Biggin Hill

Timothy wrote:

So it is in the long term interests of all of us to co-operate with ATC and airfield management as best we can; and to agree to do high speed to 4nm (and sometimes beyond) and to land long and expedite and all the other stuff so that we can retain our rights as long as possible

Clap, clap, clap…

I usually do the 1dot-below-to-1-dot above slow-down technique, but only vmc.

Antonio
LESB, Spain

Part NCO does not require a stabilised approach. Part NCC does, and allow exceptions.
Usually the operations manual will require a stabilisation at 1000ft in IFR, which is 3+NM from threshold if the glide path angle is 3°.
Flying my 172 if the weather is fine I keep the speed I can, usually 120kt
If I plan to approach in clouds I say well in advance that I will fly at 80kt . I don’t have an autopilot and flying in clouds is always a challenge in a small aircraft like that.

Thanks all. basically you have confirmed that I have an interesting challenge to deal with.
Geneva ATC are indeed very demanding and I have recently experienced two “Stuka style” arrivals from FL230-250 with ILS intercepts at very high airspeed and vertical speed..
Fortunately, the liquid cooled engine allows to chop power at will.

So here is what i have been doing lately. Given the STEC55X’s tendency to overshoot intercepts, I have degraded it to just a VS/HDG slave down the ILS.
Hand flying this is actually lots of fun, and with some practice it feels very safe to me.

1. Preset engine to the ILS parameters. 2300/26.5 so at least no need for tweaking this side.
2. Fly the ILS fast and clean (160 KIAS @ 800 fpm or 180 @ 1000 fpm)
3. Passing 4 miles, cut power, pull up to reduce speed (yes it overshoots but no ATC complaint)
4. At 140 KIAS, RPM to 2500 then gear down. Now the aircraft is in very high drag config and losing energy fast.
5. Dampen the Glideslope re-intercept using power, up to 28 inches. Takes some practice not to undershoot, but not that hard
6. As soon as stabilized and speed 120 one notch of flaps. This is like 1 mile out.
7. Finish approach.

LSGG, LFEY, Switzerland

One factor to take into account in addition to Vlr and Vfe limitations is the risk assessment of flying an approach above Vo. The light twins used in flight calibration are attempting to replicate an airliners 160 knots but because they do not want to de stabilise the approach at 4D, they will fly the approach clean down to minima. The airliner on a coupled approach would slow to 110-130KIAS at 4D. The light twin may fly the approach at a higher speed than an airliner approach speed, whether for calibration reasons or to fit in with ATC, but this speed will be much higher than the Vo of these types (around 125 -140 KIAS depending on all up mass, lower if lighter). In smooth air operating above Vo may be an acceptable risk, but if there is turbulence or wind shear it is easy to get out of the design envelope.

It’s a tragedy that only with hindsight this question becomes relevant. Whether flying at Vo or below would have helped mitigate the upset, or the circumstances were overwhelming nevertheless, is difficult to judge.

Oxford (EGTK), United Kingdom

Some do it this way



The elephant is the circulation
ENVA ENOP ENMO, Norway

When I was flying out in Portugal, there was a guy that flew an Extra and a Pitts and almost always did a loop on very short final. I remember speaking to the tower controller over a few beers once and asked if the guy asked permission to do this and they said he did not – but they couldn’t find a rule that would preclude him from doing it.

United Kingdom

Wow, magnificent flying in the Rafale!

Pirho wrote:

did a loop on very short final. I remember speaking to the tower controller over a few beers once and asked if the guy asked permission to do this and they said he did not – but they couldn’t find a rule that would preclude him from doing it.

The rule in Canada:

602.27 No person operating an aircraft shall conduct aerobatic manoeuvres

……… (e) in any class of airspace that requires radio contact with air traffic services unless the appropriate unit that provides air traffic services is advised that aerobatic manoeuvres will be conducted; orQuote
Home runway, in central Ontario, Canada, Canada

Pilot_DAR wrote:

unless the appropriate unit that provides air traffic services is advised that aerobatic manoeuvres will be conducted

Maybe he did so?

ESKC (Uppsala/Sundbro), Sweden
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