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ANOTHER LESSON IN "BUMP TOLERANCE"


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As of late I have been flying in minor turbulence slowly building my "bump tolerance".

 

yesterday was 32deg and by 6pm wind had all but gone although the sun still out and it was still sitting at 28deg. A friend had came up for a fly so we took off in to some rough air.

 

was alot of convection with moderate chop threwout,we flew 17.7 NM S/E at 1500ft amsl and as we approached his farm ,located in cooke plains/mallanong(10kms from lake alexandreana)we encounted some harsh moderate turbulence.Iwas needing to constantly adjust throttle from full to idle!! it was very unussual for me to see the nose in a high angle of attack with full throttle at my recomended climb speed of 50 knts and the vario showing we were decending at 400fpm?We climed to 3200 ft but still rough, Also was times I was holding FULL ailron with full rudder waiting for her to level (seemed a life time).

 

Once we were away from his farm(should mention his farm is littered with salt pans)we were back into minnor bounce,s and light chop and did not expect anymore surprises?

 

however as we approached My strip we flew over some scub decending from 2500ft with 4000rpm set,and suddenly the engine note changed? it went quiter with a slight hum/vibration,my pax instantly turned and stared at me and held the A/C frame, Also it felt like we were..hmm id say floating? I advanced throttle and it was normal again (it lasted about 5 secs) I leveled at 1000ft and put her into some circuts and every thing felt normal? we landed and then debriefed,inspected the plane (engine and prop all good) so we both feel we hit a spot of low-pressure and the thrust became unloaded?(if that makes sence?)was really wiered ..?

 

was doing so much worrk my arm and wrist were throbbing..lol

 

 

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Sounds like you were flying in some crap there FM. The engine note will change like that in gusty winds as the airflow changes into and around your propellor disk.

 

The aircraft has a lot of "natural stability" so try to relax on the controls and do LESS when its bumpy. Set an rpm that keeps the IAS roughly around Turb penetration speed and leave it there, don't try and "fix" all the VSI AIS fluctuations.

 

You will be very very busy if you do, and you won't be having any fun, which after all is why we are there.. But above all, remember the aircraft is "stable" it will ride out the bumps much better than you will.

 

Keep the speed up on the approach and keep turns shallow when low to the ground. It doesnt hurt to do a dummy approach at high speed (but below VA) to assess the conditions, winshear etc.

 

Enjoy mate...;)

 

 

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There won't be areas of low pressure of any significance as air flows from high to low to quickly to allow something like that to exist without violent rotary motion ( like a twister). For rising air masses there has to be descending air currents somewhere else, so you get pushed up sometimes and down other times A rising air current will lift any size plane if it is extensive enough to provide a big blob of rising air. What you were experiencing was probably due to the differing surface temps existing on the ground at the end of a hot day. You have to maintain a safe airspeed as a priority , but don't chase it too closely and don't change attitude violently. Make big power changes first and if ( for example) your airspeed stays too low for comfort you will have to lower the nose and lose height. This can be a real problem if you are approaching rising ground. remember that the air current cannot descend through the surface of the earth, so when you get lower you should be better off. Under a storm cloud this can have other complications ( down burst) but a U/L should not be in that situation. Nev

 

 

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Under a storm cloud this can have other complications ( down burst) but a U/L should not be in that situation. Nev

Nev, I would argue that any situation that required "Big power changes" and losing height to gain speed is no place for an UL either. This implies flying in wind gust's grater than the usable speed range of the aircraft, ie, stall speed to VNE, or at least stall speed to VA. In FM's 2 stroke lightwing that would require flying in wind gust's of 30 or 40 knots. Thats GUST's not windspeed. Who in their right mind is going to fly a UL in those conditions.

Gust's related to 'thermal' turbulence are generally not strong enough to cause prolonged changes in IAS to the point where "big power changes" would be required to maintain a safe flying speed. If this is required, then I reckon you shouldn't be there in the first place.

 

Of course when on approach in gusting winds, then power MUST be used to maintain that safe speed due to the lower speed and less height available to "lower the nose to gain speed"

 

 

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On a hot day your plane will probably only climb at 600 fpm?. Therefore if you get a downdraft of more than 600 fpm you will have to descend to maintain a safe speed, even if you have full power on. In turbulent conditions you would have to maintain a bit extra for stall margin and manoeuvering capability. I generally say hold an approximate level attitude and let the plane go a bit here and there without trying to keep it precisely at the desired altitude. The times I have had to make a large power change is when you are under controlled airspace and don't want to go up into it. The type of conditions where this is likely to happen is with a strong breeze and a situation where you get orographic uplift due to terrain. I have had this in tassie where I have gone from 3,000 feet to 6,000 feet with power off, and gliding as fast as was safe, at the time. Nev

 

 

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I would suggest doing some more solo time before taking a non-instructor passenger again... Just to be safe. It sounds like you are experiencing some challenges with your flying... IMO you should not complicate this with being responsible for someone else's safety.

 

 

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Nev, I would argue that any situation that required "Big power changes" and losing height to gain speed is no place for an UL either. This implies flying in wind gust's grater than the usable speed range of the aircraft, ie, stall speed to VNE, or at least stall speed to VA. In FM's 2 stroke lightwing that would require flying in wind gust's of 30 or 40 knots. Thats GUST's not windspeed. Who in their right mind is going to fly a UL in those conditions.Gust's related to 'thermal' turbulence are generally not strong enough to cause prolonged changes in IAS to the point where "big power changes" would be required to maintain a safe flying speed. If this is required, then I reckon you shouldn't be there in the first place.

Of course when on approach in gusting winds, then power MUST be used to maintain that safe speed due to the lower speed and less height available to "lower the nose to gain speed"

Merv's correct. Be very careful not to exceed your Va speeds by trying to maintain altitude without reducing your power in updrafts. (rough guide: Va = 2x your clean stall speed). A 'safe' turbulence penetration speed is roughly midway between Vs and Va. But, it sounds as though you need a bit more control co-ordination practice so that you can maintain wings level with far less effort on ailerons. Gusty conditions always test low time pilots, and it needs control inputs with your feet and hands together. Like all flying - you need endless practice to detect small changes in pitch, roll and yaw - and to input controls early enough to prevent it going further. Don't sweat it - it takes time and practice.

 

happy days,

 

 

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flyer me said: As of late I have been flying in minor turbulence slowly building my "bump tolerance

 

If you want "bump" practice find a reasonable sized fire and circle above it, not too close. Did that in a glider once and the vsi went off the scale upwards and seconds later off the scale downwards. One wing could be in 20kts+ lift and the other 20 kts+ sink for very sshort periods. Longer periods and you would be doing rolls above the fire. If things get too rough, you can get out in seconds. As for me, I'd be off looking for a bigger fire. Some gliders are stressed for aerobatics for which I am endorsed to do.

 

 

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Turbulence is never really fun( for me anyhow) Tighten your seat belt right up and get out of it if you can. It fatigues your plane and you. If you like pulling "G" do some aero's in the right plane with the right instructor. That type of plane is built and serviced to take it.

 

Learn about where the worst turbulence may occur and avoid it. I have lost friends in good strong aircraft that has broken up in turbulence. The air is your medium and you must know and understand it. perhaps one day someone may say "are you a pilot" and you might reply "I like to think I'm an Airman as well". They would probably think you are mad but don't worry... Nev

 

 

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cought up with my friend and instructor today,he was passing threw and stopped off (as he does every year)for a rest before continuning on his x-mas holiday.

 

after a lengthy discussion he decided we would take the lightwing for a fly..hmm are you kidding?(if the wind sock is moving I stay on the ground)wind was /is around 14nts S/W and is 30+ deg so I knew it was going to be rough.. NOW to clarify speeds - VNE=102knts turbulance speed=75knts and my cruise speed is always 60-65knts. we flew localy here and it was a whole lot rougher than the other day!!!!!!!!!!!! again using all controls inc throttle and after 5 mins of him watching me handle it He smiled and said your making it worse than it is!! your trying to keep it level at altidude 100% of the time instead of letting it be and settle itself..what was going on (the same as the other day) was id be cruising at 60knts at 2000ft then as soon as I hit a bump I was on the controls,when we were sinking Id pull the nose up and as the speed was lost would be opening the throttle...what he showed me was to just let it be and trust it will fly out of it,, if you feel your getting to low apply power but dont climb..and also even though it felt like some nasty turbulance he mentioned it was still only minor and to stop fearing a structual damage..he said the lightwings are great in thermals as you can gilde with them? He mentioned the huge wing area on the lightwing makes it feel the bumps a lot more than a jabi,or my old supercat but thats fine.."deal with it" (his famous words)

 

anyway after loosing a couple of killo's in sweat and after 1/2 hr riding the wind sheer and thermals we came in for my most exciting appproach yet,got to practice(in my lightwing) my crab aproach,a side slip and a wind gust while holding off , and still greased it for him,,,a pat on the back,,, and He says yet again"I want a lightwing for trainning"...awesome day now to reflect on that 1/2 hour of "bump tolorence"sweeeet I love learning

 

P.S stay away from salt pans/lakes on a hot day unless your a glider pilot?..lol

 

 

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Instructor is right, just "ride" the bumps, one will take you up, the next will take you down, no big deal....

 

Lightwings are one of the strongest ac out there. Of course every ac has their limits.

 

 

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Just keep practicing and move yourself into strong and stronger turbulance. That leads into a further topic. Pilots tend to fly in their own comfort zone and when big extra demands are place on them, some I think, just "crack up". This is evidenced for example when I read about engine failures and see the pilot has crashed into a paddock big enough almost to land an A380. Seen this a number of times. Bet the pilot hasn't practiced forced landings since getting his lic.-it never came up in any BFR I took. Then the fear factor comes in when the engine stops and he panics. I first learned flying in gliders and every landing is like a forced landing and loving it. Taking up power flying, I got a bit nervous at first, having to manage an engine and throttle position on landing as well. The thought of going around was never an option before and now it was something to worry about.

 

There is not enough ongoing training with regard to flying in unusual attitudes [get an aerobatic endorsement], landing in big cross winds, being prepared mentally and physically for an engine failure. That doesn't mean waiting for an examiner to tap you on the shoulder forcing you to be current in all this stuff. Go out and practice it yourself-regularly. I do, it's fun, and gets you out of tight spots without any panic attack.

 

 

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There should be a sequence that covers a lot of pilot skills that you can practice. It's quite concievable that a lot of people don't give much thought to limit crosswind landings, steep turns. Steep gliding turns forced landing practice, stalling off a steep turn, power on and power off, after they get their licence. You are not the best pilot you will ever be after you get your bare licence. It's a safe starting point.. If you don't maintain your standard how will you improve it? Practice and extra learning will consolidate your existing skills base and you improve on that by learning extra skills and more knowledge.It goes on forever but just flying the same standard is not an improvement. The more you know the safer you are. Nev

 

 

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Please do. It may be inclined to drop a wing and the more "G" you have on the more likely that is. Pulling"G" is the same as having more weight as far as the wing knows. It is called on to provide extra lift, so your angle of attack has to increase.. If you have been taught how to recover properly you will not spin or flick. You have to reduce the angle of attack quickly. If you are not taught how to recover one day you may inadvertently get caught. Any time you are wanting to practice something you feel unsure about, do it with an instructor. This way you shouldn't be doing a wrong technique. Incorrect technique can creep into peoples flying. One of the reasons for a periodic check Nev

 

 

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As a low hour pilot I do practice those things by myself but haven't been game to stall it off a steep turn, wouldn't that potentially throw the plane into a spin? I'll grab an instructor for that one

 

That is the most likely time you will spin and go in is while doing a circuit. You are doing your circuit, you are using the radio, your concentration is also diverted to conflicting traffic and slowly your airspeed washes off. Your turn onto final is a bit late so you increase the angle of bank, your lower wing keeps increasing angle of bank which you counteract with more opposite aileron. At this point you signed your death warrent and if that is unclear, read a book on principles of flight.

 

 

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Good God - you'll scare the willies out of the newbies talking like that! Yes, these things may happen but it is natures way of keeping the rest of us safer.

Some pilots don't end up with the happy option of just being scared.

 

 

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