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Posted
3 minutes ago, Old Koreelah said:

Very interesting. A couple of new ideas there: Pulling flaps on a steep turn, dumping smoke to check spray drift.

in another video he said the flaps buttons are on the stick, he uses them to jump over the trees.

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Posted
11 hours ago, Old Koreelah said:

Very interesting. A couple of new ideas there: Pulling flaps on a steep turn, dumping smoke to check spray drift.

Depends on a few things, particularly flap design.

 

Firstly flying straight ahead:

Fresh from soloing and with a barrel roll and flight below ground level with the instructor in a local drain, I was cruising along across a swamp in a V115 Victa and  had been watching the bank ahead. On top of the bank was a row of pine trees I hadn't been noticing and I was too close to turn. I pulled the stick back and the nose climbed up the pine trees, got to about half, and wouldn't climb any more started to show signs of stalling so I had to lower the nose slightly. I realised I had maybe 20 seconds to live, a long time, and was thinking about my life when I had a lightbulb moment "Steepest climb/slowest forward speed = full flaps. I yanked on full flaps instantly, the nose went up the pine trees like an express, and it was over; lifetime lesson learned.

 

A few decades later I was doing touch and gos in a J170, forgot to pull the flaps up, gave it full throttle, and rather than the elevator effect of the Victa, the Jab's nose climbed straight up; it wanted to go over on its back. After some strong pressure on the stick to keep it stable and flying, another lesson learned. 

 

Nothing wrong with the Jab, just totally different reactions to full flap input.

 

Second, in the turn

Straight and level results in 0 G straight down through the floor

A Rate 1 turn (30 degrees) results in 1.15 G through the floor which is now pointing outwards

A Rate 2 turn (60 degrees) which RAA designates aerobatic results in 2 G through the floor now pointing further outwards.

 

An aircraft stalls when the wing exceeds its maximum angle of attack (around 15 degees); in our basic flying the stalls always occur at the same co-incidental speeds, and we are taught on the speeds because we have an accurate ASI and not an angle of attack indicator.

 

When we are in a turn, with increasing G forces the stall factors change. The aircraft is not just flying but forced down through its floor, so the stall will occur at a faster to much faster speed.

 

A good example of where this catches people out is the turn onto Final. They might be doing 80 kts, but realise they just missed the turn and pull the stick hard back, and down they go, killing all on board because the stall speed with the Gs they pulled on required a much higher fllying speed.

 

I realise you know all that, but the point I'm making is that the may have flaps and configuration specifically suited to tightening turns and jumping trees, so I depends what the Jodel's got.

 

The Victa has interconnected airlerons and flaps with both systems functioning as both ailerons and flaps when operated.

The J170 has big flaps and 40 degree angle to handle the hotter air of northern Australia. Maybe I would have succeeded better with half flap.

 

 

 

 

 

 

 

Posted

Watched a croppy last night on Outback Pilots (7mate), skimming along, wheels in crop. What intrigued me though, was the way the cowboys and cowgirl threw the Robinson R22's around between the trees, rounding up cattle. Amazed that there aren't more crashes. More agile than bikes or horses.

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  • 2 weeks later...
Posted
On 15/08/2023 at 1:47 PM, Thruster88 said:

How flaps work

 

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True BUT...

If you have no flaps set and are in steady straight and level flight application of flap will initially create a significant increase in lift to 'pop' you over an imaginary treetop or fence ... the drag from the flaps that slows you down lags the lift in time of arrival so this is a just a blip because with fixed power and higher drag you will settle to a different airspeed and your climb gradient will return to that of your graph where you are at a lower climb gradient than than you could in theory have if flapless.

Posted

The lift you get  with flaps extended always results in a worse L/D ratio than the clean wing.  Nev

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Posted

I would think pitching to convert airspeed into short term obstacle clearing height gain would be just as effective as using flap, maybe more so? If we are concerned about obstacle clearance we would be climbing at best angle of climb speed Vx, normally about 1.3 times clean stall speed.

Posted

If ever I'm low on speed near the  ground I don't get out of ground effect until I get the right speed. . That's saved me a few times.  Nev

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Posted

That's what you do IF you don't have enough speed to be safe. Another option is to put it back on the ground and try to stop. Nev

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  • 2 months later...
Posted

Nothing beats manual flaps for gaining lift quickly, especially if trying to make minimum radius turns. The earlier Cessnas had a 4 position flap lever and on the 180 & 185 this was very reassuring as you kept your eyes outside while extending or retracting flap. Kept you much safer. happy days,

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Posted

Getting bounced into the air prematurely is  not uncommon with an Auster's rubber bungee U/C if there's a hump in the field surface. Any proper endorsement on that type will include mention of this and the proper technique to apply  is to stay in ground effect till you have a safe speed then climb.  Nev

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