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All of the discussion on this thread seems to be focussed around tailwind ops for GA aircraft. In fact, there are many airline transport operations (including four engined heavy jets) into mountain/fjord airports which require tailwind approaches for good and valid safety reasons, such as: terrain clearance, severe turbulence in specific meteorological conditions, downdrafts in katabatic winds at airfields with glaciers nearby, etc.
The need for tailwind approaches was recognized in the certification to FAR 25 rules of the Dash 7 for steep approach capability, as an airplane which could be found in many of the more unusual airfields of the world:
Courchevel, France Aspen, CO London City, LCY Unst, Scotland Narssarsuaq, Greenland Sondrestromfjord, Greenland etc., etc.
In order to approve the 7.5 degree approach the certifying authority (TC) defined an ultimate requirement for the aircraft to capture the steep approach slope from 2 degrees above the glide path, with one engine inoperative, i.e. a 9.5 degree, three engined descent capability.
When operators subsequently expanded the requirement for tailwind approaches at high altitude airfields, the Dash 7 was eventually certificated for 7.5 degree approach and landings in 20 knot tailwinds at runways with elevations up to 10,000' ASL plus, including with one engine out.
The procedures are contained within the approved AFM and do not demand exceptional pilot skill, of course. Although I stand to be corrected, I am not aware of any runway overrun accidents in the 30+ years of Dash 7 fleet operations wordlwide, but no doubt somebody can prove me wrong!
Interesting points, with which I agree. I would point out though that the original question was asked in the context of a Cessna 172, hence the focus on GA aircraft. My limited experience in the wonderful Dash 7 has me thinking that it is profoundly more capable of handling a tailwind with predictable handling than a 172 - spoilers for one reason!
I do not suggest that tailwind operations are not necessary from time to time, particularly in Part 25 type aircraft. I do still suggest though that the average C172 flight probably does not need to operate downwind, and such conditions could rapidly exceed the skills of an average 172 pilot.
I think it is worth the effort in such a forum to attempt a balance between the skill set of how to do something at the edge of the norm, as compared to the skill of deciding not to try, because there is not real need!
Reading these posts makes it look like flying and aeroplane is akin to rocket science, and that the venerable old 172 is similar in complexity of operation to the space shuttle.
Pull back, houses get smaller, push forward, houses get bigger…. You can teach a monkey that (this can be proven my the number of monkeys I know flying fast, shiny, tubes full of people)
Experienced flight instructor usually means experienced in instructing, not piloting an aeroplane. There is a significant difference. Most instructors have never landed or taken off down wind, and think it’s dangerous and therefore wont/can’t teach it. Landing and taking off down wind is necessary at some airports, and is done quite safely in far heavier metal than a 172.
Quote:
.......to do something which the flight manual would not recommend
The Litigious American culture/environment are the main drivers of GA aeroplane flight manuals. Although I can not suggest disregarding the manufacturers recommendations, the fact is, they recommend nothing for fear of being sued by some idiot. Most of the info in GA flight manuals is comparable to the ‘Caution, Hot’ label on the lid of my McDonalds coffee.
And coming in down wind at minimum approach speed? how are you alive still? I'm thinking dumb luck.
My limited experience in the wonderful Dash 7 has me thinking that it is profoundly more capable of handling a tailwind with predictable handling than a 172 - spoilers for one reason!
Which triggered one of my neurons to connect with the other -
Is there an aircraft in which the spoilers are actuated by bringing throttle(s) to full retard? Or is it my imagination?
I nearly killed myself landing a Cessna 150 Downwind.
Cocked it up. Landed in the wrong direction. (no radio or traffic).
Got alarmed by the high GS so went round. Immediate left wing drop-30 degrees at least. (I was slow!) Got it with the rudder, thank feck!
Skated right across the airfield with no speed or height at 40 degrees of left hand down compared to the runway and still full flap, towards trees, buildings etc.
Is there an aircraft in which the spoilers are actuated by bringing throttle(s) to full retard? Or is it my imagination?
Full retard on a Dash 7 would be full reverse, a place where most pilots would not get to very often (potentially damaging to the aircraft). Full retard on many other types would be idle power, which can also be used in flight (where spoiler use is not ideal, in most cases).
I have limited knowledge of systems in which spoilers are actuated by a combination of power lever position, and weight on wheels switches. This was an element of a serious crash of a DC-8 operated by Air Canada decades ago, where the aircraft was bounced on landing, deploying the spoilers, and attempted to fly away with fatal results. The undesired operation of the spoilers contributed to the crash as I recall.
Spoilers are a great system for control of the aircraft, but their operation, or failure to operate as desired, has serious safety considerations. This, in particular, because, in many cases, the position of the spoilers cannot be seen by the pilot. Most aircraft would have spoiler position indicators. I did once fly a Mooney, whose spoilers (speed brakes) had a mind of their own. It was not a big deal though, as their effect on the flight of the aircraft seemed very limited anyway!
Sorry to dash (pun intended) your patent ideas... I don't think you want the liability of this one!
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