Microlighters

Yesterday afternoon ; Time: 15:20 ; Wind: crosswind ; Wind speed: 10 km/h ; Gust: 18 km/h ; Temperature: 23 degrees Celsius ; Airfield: Petit

It was a good day for flying. Entering and lining up runway 21. Get, set and go. Full throttle with a gentle climb out. On take off I did experience the normal bumps and side slips and at +- 500 feet AGL something happened. It felt as if my plane was suddenly plugged out of the sky. My feet came of the pedals, the bar was pulled out of my hands and my “poepol” was closer to the wing than to my seat. Within seconds my plane was in a nose down attitude with not much height to recover. Possible reason I think is the sudden loss off power in the climb-full power to no power. There for the tuck. For a moment I was disorientated but as soon as my “poepol” hit the seat again it was power and bar forward to recover from the situation. Luckily I allways tighten my seatbelt which I think save my life.

What do you people think was the possible cause for this???: a) Down draft b) Wind shear c) combination of a and b or d) something else

I’m flying now for the last 6 years – did fly in really testing weather and wind before - but this is the first time it ever happened to me.

Lessons learn: a) Always makes sure that your seat belt is tight around your waist and that its 100% clipped in. b) Practice your stalls on a regular basis c) Take deep breaths and enjoy your flying

Cheers
Hendrik Loots aka Skin

downdraft.....
Full throttle, as straight as possible, bar forward and hope.

Skin wrote:Possible reason I think is the sudden loss off power in the climb-full power to no power. There for the tuck.

What about e) None of the above. Check out viewtopic.php?f=16&t=10938&start=30#p113628.

Downdraughts is just that, but you are still flying. Windshear will cause a stall, but a power stall, and not a nose dive.

The reason from full power to no power was because of the situation. My feet came of the throttle completely because of the sudden loss in height. I want to know the possible cause is of this sudden violent loss in height???!!!!

Skin

Skin wrote:The reason from full power to no power was because of the situation. My feet came of the throttle completely because of the sudden loss in height. I want to know the possible cause is of this sudden violent loss in height???!!!!

Skin

Ok, I understand your situation. I have heard of turbulence (real bad ones) kicking a pilots feet off the pedals. Might be that, and then the loss of power caused your "whip stall" and subsequent loss of altitude. All I can think of.

Downdraughts and windshear will cause the loss of altitude, but not that severe or uncomfortable.

My opinion.

What happened on the rest of your flight, was it turbulent??

2 weeks ago, mid day, temp around 10 degrees, windsock stable, so reckon same as a morning flight. QNH = 1035, pax and pilot 200kg full tank.

200m after take off, the most violent lift- 500fm/m followed by a vacuum of same, for about 10 minutes. 912S working hard to maintain stright and level. I almost considered going to 2000 agl and using my 3.5 hours endurance before landing. The same pattern continued till I turned to land. Briefed pax about scrambling if any wipe-out, using lots of runway at high speed.

New meaning to to me the word lift and sink.

Surely fixed wing pilots must go through the same experience - or is a trike more susceptible to more violent dips? in same conditions described above?... Scary stuff. Sounds quite rare but does happen

Any idea what the wind strength etc was at or above the altitude you encountered the turbulence? Can you recall if you felt a sharp increase in air temperature?

I had a moment in the Bantam a few months ago, posted some stuff but cant find it. While doing circuits at FAAP (which had been going very well) the last circuit that i flew, i just had a bucket full of no lift. NOT violent, just would not climb, now the interesting part is that i hadnt felt anything amiss for the previous 10 circuits. No matter what i did i just could not get altitude. Radio the clubhouse - tell them im doing a low level circuits, all pressures and temps good, just could not get lift !! landed and all was cool. weird....

Skybound

No, I'm not sure what the windspeed was at that specific altitude. I also did not feel any increase in air temperature but a hell of a increase in body temperature with symptoms of dry mouth and increased heart rate.

Cheers Skin

Skin wrote: a hell of a increase in body temperature with symptoms of dry mouth and increased heart rate.

I bet - anyone of us would have been exactly the same and in serious need of when back on terra firma.

The conditions are ideal at present for Berg Winds and perhaps even though you did not have huge wind on the ground - at a few feet up - some scary winds were a pumping. At the coast can be calm on ground and at 500ft have a 30 knot bergie. The fact that you had almost a 100% gust factor (10->18) would have indicated something was brewing.

My 2c worth and I need change

Skin, when I took off after you landed I experienced the most lift ever in my trike - I shot up skywards at one moer of a rate of climb. I couldnt think what caused that because on my next touch and go, there wasnt near as much lift. What could it have been???

No idea Nkwaas, no idea....!!!

Hi Skin,

You mentioned all data, but what was the qnh??