I’ve just been reading this and I guess that pilot may have been way over any reasonable speed, but would it not be the case that in most RG types you can slow down while on the glideslope? There is the engine rapid cooling risk, which is why one tries to avoid this sort of thing.
Maybe FG planes without air brakes have additional issues there?
Necessary…. it is a means to an end. A good means though.
The saying comes to mind: “you will never be criticised if you go around, but you will be criticised if you continue the approach and it goes wrong”…
But, with the average GA flyer that flies 20(?) times per year. How stable is the approach going to get? You’d have to keep pretty loose margins to define stabilised/unstabilised. On the other hand it would be cause to say you actually need tighter margins…
In commercial/airline flying the daily frequency means that every approach will be flown pretty much exactly the same. To certain extent. E.g. Vapp -0/+2 kt, even without auto-pilot.
I try to fly every approach the same, with only approx 300h, and a tricky airplane (Comanche 260C) to land on a short home runway (650m in mountainous terrain) you need to really be on the numbers all the time which is why I try to stay on the numbers every time regardless of Runway length. (of course taking into account any crosswind)
My training was very pragmatic, leaving out as much “big language” as possible; so I am a bit unclear what exactly is meant by a “stabilised approach”. If it means “on final, all parameters ought to be at reasonable values, particularly height and airspeed” well that seems very basic to me. If too low or too slow, add power (and hope and pray it will come) – too high or too fast, go around. Easy, isn’t it?
Pour la petite histoire: on the first circuit of my check flight, the examiner kept on talking to me, so much confusing me that on final I was still at the circuit height of 1100’. I “slipped off” the excess height and landed only slightly long, which was no problem on the longish (600m!) runway. I still wonder if he did it on purpose, but he did comment “your side-slips are quite ok, next point!”.
Talking of that: I once heard that one should aim to be 500’ AGL on final, any comments? While it generally works for me, it seems like over-generalising.
I think the heavier and complex an airplane is and the higher its appch speed is, the more important a stabilized approach is.
I always make an estimate based on actual weight on approach forva VFR landing and then try to nail the airspeed.
Short field approach speed: 77 KIAS at MTOM
minus 1 kt per 100 lb under gross.
For simplicity i use 75 with two on board and 73 if the tanks are only half full.
My first instructor used to say: if you can fly 70 all the way down, you can also fly the required 68 kts. And it’s true, in calm conditions you can always nail the speed if you trim correctly.
IFR i fly as fast as the traffic situation requires… anything between half flaps at FAF and 115 KIAS and no flaps and 160 KIAS. The 4-blade prop has such a huge braking effect that i always arrive at the threshold below 80 with full flaps.
Flying a fixed gear Jodel DR1050 tailwheel, usually landing well below MAUW of 740kg, I’m dubious about stabilised approaches if that means a steady speed and rate of descent from a mile out. In a gusty crosswind I’m rocking until I get the upwind wheel on the ground. To fit in with traffic, I often fly the approach at near VNE in calm conditions, and turn tightly onto a very short final.
What is essential is to have the speed at least the recommended approach speed, and height to suit for desired touchdown point. Then hold off, not getting into ground effect until recommended “over threshold” speed.
I’ve a YT video of a “Fast approach to 06” Inverness where the ASI can be seen.
What’s the latest that you can sensibly choose to go-around? Up to that point, if there is a reasonable chance of landing successfully then you’re potentially throwing away a viable approach, and given the responsiveness and maneuverability of small aircraft there’s a lot of latitude for adjustment even at a relatively late stage. Starting a go-around whilst passing over the hedge generally seems fairly relaxed to me.
Personally I enjoy flying glide approaches. I intend to sideslip until close to landing, and if I have to add power I consider I’ve ‘failed’. I try to do a go-around most flying days. I’m not sure that flying like this makes me safer – I could argue it both ways – but it’s a lot more fun. Also, when your approach speed is a few score knots, changes in wind speed and direction over the last few hundred feet are going to make far more difference to you than they will to an airliner touching down at 140 knots so the concept of being ‘stable’ at 500 feet has much less bearing on whether you’re likely to be ‘stable’ at 30 feet, which is where it really counts.
I can see that a ‘stabilised approach’ with gates could make sense for very slippery aircraft or jets with engines that are slow to respond, or for landing on shorter runways or runways with no go-around options. But for the aircraft I fly I see the concept as a travesty.
Jan
so I am a bit unclear what exactly is meant by a “stabilised approach”
Big aeroplane stuff, large aeroplanes have considerable inertia and jet engines don’t produce instant power as the turbine has to spool up therefore; when on the approach to ensure a successful landing, everything has to be in the box some distance before the final event i.e. stabilised, if not, you go around at that point. With a low inertia aircraft you can stabilise it in a very short time/distance so the concept of a stabilised approach is quite different. I remember flying an ILS in a PA28-140 at 147 mph and touching down at 70 mph, all achieved in the final 200ft.
Thank, @Tumbleweed, all clear now.
