Airbus groundspeed mini & unstable approaches
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What he meant is that it is useless to share your overall experience to advocate a point. If something is right, it is simply right regardless of you having 10, 20 or 30 thousands on type. The concept of preaching / teaching something because it comes from a certain amount of hours of experience on the aircraft has led to a certain amount of events in the past and that is one of the aspects that modern notechs core competencies try to tackle. Don't get me wrong, sharing personal opinions & techniques is great and often very helpful but there is no point in justifying our wisdom by the fact that it has worked in the past 20 or 30 years.
Hello sabenaboy 
I was not referring to any of your subsequent guesses, (and thanks for the mild abuse), but this comment from your previous post caught my eye:
All I know is; much cleverer (test) pilots than me developed the G/S mini system.
I was not referring to any of your subsequent guesses, (and thanks for the mild abuse), but this comment from your previous post caught my eye:
Why am I better then A/THR? Because I'm not stupid enough to blindly chase the Vapp and go to idle at 300' ft
Only half a speed-brake
What is this, APU INOP situation? Someone should either connect the external aircon or at least open 2R, pronto. 
Gents, GS mini is a simple trick, although embedded in the EIS. It is neither a system nor a part of the FBW. Used before any SA Airbus was drawn on paper. As you expect the HW to drop off with a subsequent loss of airspeed due to the aircraft's inertia over the ground, you brace for that with extra buffer ontop the Vapp. Delta = HW(act)-HW(rwy). No less, no more. Benefits? Plenty:
- somewhat stable N1 along the approach
- marginal (for one flight) fuel savings
- significantly reduced noise footprint
- avoid the need to increase N1 into the flare, allowing for non-ace like handling
Yes it does provide for a low GS (and E-kinetic) threshold, but that is a completely unnecessary, fancy explanation why you want to do it, not a design objective. Well maybe, if you insist on overcomplicating things - that is usually my role!
Once again, carry an additive to Vapp, so when the airspeed drops with the HWC dying, it drops where you want it to be for the landing.
--- edit? funny fact of the day ---
"GS mini" function does actually have a tolerance of 10 kt for the delta HWC. In fact, delta(Vapp) = hwc.act - max(10 kt; hwc.rwy) / negative results are disregarded. Layman's terms:
The correction does not go below the normal Vapp;
The correction always assumes at least 10 kt HWC at the runway, regardless of the actual entered data
Gents, GS mini is a simple trick, although embedded in the EIS. It is neither a system nor a part of the FBW. Used before any SA Airbus was drawn on paper. As you expect the HW to drop off with a subsequent loss of airspeed due to the aircraft's inertia over the ground, you brace for that with extra buffer ontop the Vapp. Delta = HW(act)-HW(rwy). No less, no more. Benefits? Plenty:
- somewhat stable N1 along the approach
- marginal (for one flight) fuel savings
- significantly reduced noise footprint
- avoid the need to increase N1 into the flare, allowing for non-ace like handling
Yes it does provide for a low GS (and E-kinetic) threshold, but that is a completely unnecessary, fancy explanation why you want to do it, not a design objective. Well maybe, if you insist on overcomplicating things - that is usually my role!
Once again, carry an additive to Vapp, so when the airspeed drops with the HWC dying, it drops where you want it to be for the landing.
--- edit? funny fact of the day ---
"GS mini" function does actually have a tolerance of 10 kt for the delta HWC. In fact, delta(Vapp) = hwc.act - max(10 kt; hwc.rwy) / negative results are disregarded. Layman's terms:
The correction does not go below the normal Vapp;
The correction always assumes at least 10 kt HWC at the runway, regardless of the actual entered data
Last edited by FlightDetent; 15th Jun 2019 at 19:20.
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I think the sceptics of GS mini and/or admirers of older method perhaps forget how much work load is there in that.
Most people may have forgotten this. As against this with GS mini you just fly the target speed.
"Note: To prevent increased landing distance due to high airspeed, bleed off airspeed in excess of VREF+5 knots + gust correction when below 200 feet AGL. Maintain the gust correction to touchdown."
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Exactly! When you are flying 90+ hours a month with minimum rest, and you are being monitored up the wazoo on every single tiny detail, just keep it simple.
