Scary take off in the bushveld 14h00 and hot

[BONZAI BELL]

Had a very scary experience on take off on a landing strip in the bushveld. It was a grass strip , and the grass slightly longer than i am used to. Bushveld trees on either side of the runway. At the time of take off , there was no wind at all on ground level . the windsock indicated a direct cross wind above the trees. I lined up for take off, pre rotated to 180rpm and went for the take off. I felt the grass holding me back slightly, but soon checked that my airspeed meter read 55mph. i then decided to pull back on the stick slightly , to get airborne. this happened , but once i was about 4 metres above ground level, and also level with the tree tops, there was a bit of turbulence , and i was pushed back to the runway. The moment i realized i was going down, i went for full turbo power and stick slightly forward. A quick glance at my airspeed indicator, i realized that this was now flying behind the power curve. I made a smooth contact with the runway with my tail wheel and just kept the power on and the stick slightly more forward. Seconds later , i was airborne again ,but this time flying a meter above the runway for another 100m. Gained sufficient airspeed, and then got altitude.
Now i need some advice. Was i in too much of a hurry to get out of the grass?
The fact that there was no wind on the runway, did my rotor not gain sufficient rpm for lift off?
Should i have stayed on the runway longer and taken more note of rotor rpm before trying to take off?

[MAGNIficent]

Swannie, the instructors will be able to give the best advise, but here is my input.

Bushveld - high temperatures, so high altitude density is a factor- plan to use the full runway.
Long Grass slow you down - Spin your rotors to maximum before you leave your brake and give full throttle for take off.(I spin up to 210 rpm)
Crosswind - Load your rotors by stick full back till the picks up, catch nose as soon as it lifts and then gentle stick forward.
Hot and crosswind - stay in ground effect as long as possible and use your turbo to gain maximum forward speed.

Should i have stayed on the runway longer and taken more note of rotor rpm before trying to take off?

The moment you left the pre-rotator, forget about your rotor speed, because you can not do anything to your rotor speed now, except fly your GYRO.

Would like the input of the GURU's as well.

[RV4ker (RIP)]

Assume it be same for Eggbeaters as for bliks - If you have a soft field technique use it. For bliks get wheels off the surface ASAP, then get to safe flying speed in ground effect then climb away. Run up against brakes, 20deg flap and rotate ASAP, then 1m above runway till flying speed, 10 deg flap and climb away... Putting the nose down just after rotate will "prevent" getting behind power curve.

[RV4ker (RIP)]

Speaking of Density Alt. This was temp on ground just before take off on Friday at FAVB 14:00B. We had a number of the temp sensors on the breakers in the minisub DB's (1000kva) shut down which happens I am told at 50+ degC....

Car probe is in direct sunlight, so possibly not as accurate as could be but it was waaay hot....

DA was 9185 ft based on elevation of 4000ft and QNH 1016... I rekon I ran 50-80% further down the runway even though there was a 8-10kt quartering headwind...

[mak]

Swannie

See how quickly one start to learn after getting your licence.

I agree with Magnificent and RV4ker, under those circumstances you should get your nose wheel off the ground as quickly as possible, but stay in ground effect as long as possible. I don't know what you meant that you pulled the stick back to get airborne, beacause we start with stick full back until the nose lift as Magnificent said, so we don't have to / can't pull it back further. Under those conditions I would also pre-rotate a bit higher than normal to get the nose off the ground a bit quicker.
You aslo might have experienced a bit of a downdraft coming over the trees if you say you had a bit of a crosswind above the treeline.
Glad your training got you out of trouble second time round by getting your nose down and building up airspeed in ground effect before climbing out, well done.

[BONZAI BELL]

Hi Mak
I was instructed on pull off , to have the stick totally back. then on the roll i would ease the stick slightly forward to get rid of the drag, and then wait to get airborne. so i did have between 25 and 50 mm to move the stick back. I think the biggest problem was , that i must have been nervous and wanted to get out of the grass sooner than i was supposed to. so i think i should not have pulled the stick back. This got me in the air, but also brought my speed down, and the moment i was out of ground effect, i came back to mother earth. Hope i am understanding what RV4ker is saying: Get off the ground ,but stay in ground effect untill you have sufficient airspeed and then climb out.It makes sense.
Thanks to all so far for your input.
Swannie

[Engelsman]

Been there done that...ground effect is my best friend i and use it all the time (thankx to my instructor Johan Waggies)) and use all the runway 2 get the speed up..

[RV4ker (RIP)]

100%.
Hold it down till vne and then ripit....

Just kidding but u get idea. Low level faster is better if you have runway then use it...