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Hi everyone,

I recently had an opportunity to fly the Jabiru J230. I had the flaps fully extended, power off and speed about 70 knots on finals, with the trim set fully back. As a part of normal touch and go, I applied full power and noticed the aircraft yaw to the left and pitch up suddenly. I immediately corrected this with a boot full of right rudder and lowering the nose. However, I was caught by surprise, and in aviation surprises are not always pleasant. As soon as I had the nose level and speed of 80 knots, I raised the flaps to 1st stage (take off) and set the trim to neutral.

 

I know, I should have raised the flaps for take-off and set the trim to neutral before applying full power, but at the time, I was caught off guard. As I felt the behavior of the aircraft to be a bit unexpected, I went back to the Jabiru manual to see if it had any special instructions on go-around, and this is what I found - Full power, full flap go-around will produce an initially strong yaw to the left and nose pitch up. These effects must be anticipated & controlled using the rudder and elevator respectively.

 

Looking at a fatal accident in a Jabiru 170 in 2016 - https://www.atsb.gov.au/publications/investigation_reports/2016/aair/ao-2016-112/ I am wondering if this is exactly what might have occurred. The pilot may have made a last minute decision and applied full power with flaps fully extended, to either go-around or land further down the runway, pitching the nose high up and yawing to the left, resulting in a stall-spin accident, which cost him his life.

 

Although my instructor had warned me in advance regarding the yawing and pitching tendency of the Jabiru J230 with full flaps, I did not expect it to be so pronounced. Having learnt from my recent experience, I would suggest that all students and experienced pilots, should practice go-around with full flaps a few times, with a certified flying instructor, or at least as a part of a check ride or BFR, to get accustomed to the flight characteristics of the aircraft they are flying. It might save your life one day, when attempting a sudden go-around while you are still in landing configuration, with flaps fully extended. 

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Hi everyone, I recently had an opportunity to fly the Jabiru J230. I had the flaps fully extended, power off and speed about 70 knots on finals, with the trim set fully back. As a part of normal

@anjum_jabiru , 70 kts is a bit hot on finals with full flap isnt it ?  I would have thought more like 65, then 60 late late (nil wind, good condix)    BTW my J230 does not have a pronounced

J230D: my best approach starts with slowing the aircraft on late downwind abeam the threshold. Carby heat on and reduce rpm to 1600, trim back to maintain circuit ht. 84kt 1/2 flap. Turn base and fly

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I've only flown a 230 a couple of times and only used 1/2 flap to T&G and didn't notice anything out of the ordinary. You should always apply full power before flaps and trim but that must be done with a simultaneous forward stick to counteract the pitching up moment with flaps extended and right rudder is always required, flaps or not on takeoff in a 230.

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Not long after buying my J170C I had a bad landing, got into PIO (pilot induced oscillation) and so I hit the throttle. There certainly was a strong yaw to the left but maybe the pitch up was masked by the porpoising I had been doing. Thank Heaven I had been taught about PIO during my GA training. Lesson learnt; Don't rush your landings!!!

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I've always found the trim will not fully counteract the back stick pressure anyhow when landing.  To be forewarned is good but always be ready to apply "enough" control force to get what you want from any plane. IT mustn't fly you.  Have enough speed also OR stay in ground effect till you do. Nev

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I often wonder why trim is used to counteract the force to apply back stick. No matter what happens during the landing you will have to alter the stick position, it will be full back on the ground or forward for a go around. Unless your trim is extremely effective you should be able to control the plane without altering it.

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I don't bother with trim at all in the circuit. Most instructors seem to train trim there but I think it is mainly to get students used to the feel of what it does more than anything else. I trim for hands of when I am at cruising altitude & leave it neutral for other flying. On landing and takeoff, climb and descent you will have to override the trim anyway unless you want to spend time setting and resetting it which is just additional cockpit workload you don't need.

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Some planes have a lot of pitch trim change  with speed change and it's not good to leave high stick forces happening and having to add even more at the flare.   Some have little variation ie the Gazelle and you could pretty much leave it in the one place.. Trimming should be second nature but don't fly on it. You don't usually trim to a turn as it's a short duration thing and you return to the S&L  already trimmed. Nev

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This reinforces my thoughts / concerns regarding flight training, in particular RAAus training. Go-arounds are not in the RAAus syllabus. I always include a go-around or two in type check flights. If you’re doing touch and goes use takeoff flap, that way you don’t need to change flap settings. The practice of retrimming on the ground will bite you one day, especially in a taildragger. As far as trim use goes, trimming in the circuit is normal practice to assist with stable approaches. There are a few GA types you need to experience to appreciate the control forces. The Yak 18T and any Cessna 100 series with 40 degrees of flap, the 180,182,185 are a handful if you’re 1 or 2 up, steep low powered approach it’s almost 2 hands until the flaps are at 20 degrees. 
The safest way to learn the characteristics is to set up the approach configuration at say 2000’ AGL and simulate a go around, you should not be learning these characteristics in a real go-around. 

Edited by Roundsounds
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Besides, it is important to overcome the urge to correct the left yaw with ailerons, but to use right rudder only. Otherwise, it could lead to a cross controlled situation. An increase in angle of attack of the left wing, without adequate right rudder input, could stall the left wing, resulting in spin to the left.

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Lazy feet are a problem. You apply corrective rudder  on take off and keep the weight off the nosewheel is good technique. If you are slow, build up speed while still in ground effect similar to what you do on a boggy strip and (have to) lift off slower than normal.  Nev

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21 hours ago, anjum_jabiru said:

...I would suggest that all students and experienced pilots, should practice go-around with full flaps a few times, with a certified flying instructor, or at least as a part of a check ride or BFR, to get accustomed to the flight characteristics of the aircraft they are flying...

Preferably at altitude.

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@anjum_jabiru , 70 kts is a bit hot on finals with full flap isnt it ?  I would have thought more like 65, then 60 late late (nil wind, good condix) 

 

BTW my J230 does not have a pronounced tendency to yaw  with full power and flap.   No more than another aircraft  I fly regularly. 

 

I think as facthunter put it- maybe lazy feet.  During takeoff, you are onto the rudder and yaw tendency like a bulldog. 

 

*** you are ready and anticipate it .

 

landing, you are probably not doing anything with your feet ,no need to . at all unless there is a Xwind.

and then suddenly you turn it into a TO with full power 

 

 

 

 

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The Go around can be  one of the most critical operations a normal pilot performs.  Critical to decide on and often difficult and demanding to execute,  requiring precise management and a high workload especially with complex types and close to other traffic. Nev

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6 minutes ago, RFguy said:

I think as facthunter put it- maybe lazy feet.  During takeoff, you are onto the rudder and yaw tendency like a bulldog. 

I guess, it took me with a bit of surprise, as I did most of my flying in a LSA, and few hours in J160. I guess a bigger 3300cc engine in a J230, means more power = more left yaw = more right rudder 🙂  

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anjum_jabiru, I hope my previous  post there was useful.  70 kts is too hot IMO for that config. Vflaps is only 84 kts. no much airspeed margin to dive to control an updraft taking you off the glide slope (and increase airspeed)  in order to stay on a stabilized approach in  thermally conditions.  anyway, I am sure with practice you'll be fine. 

 

that's the thing, isnt it Nev, on takeoff, you are on it.  your brain is tasked well with keeping it flying straight with the torque and wash yaw. 

 

But  landing with good condix you go from one type of "subroutine" , to a go around is a very different flying configuration and objective . I have at times tried to go around with full flaps (wont climb at all)  and also forgetton carb heat (wont climb well at all either).  I bet a combination of full flaps and carb heat in a go around is a recipe for ending up in the trees at some places !.

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When things go wrong you need to put more work in. No landing is complete till the plane  is stopped and secured.. IF you are ready (prepared mentally) you perform better. Your landings might have become prescriptive where things are supposed to always go a certain way and you have been getting success from a one  two three sort of performance. THAT can go stale. Landings are not like push ups where you get better just by doing more. Students also don't like it when you give them a go around before touchdown as they miss out on a landing.  Use whatever control is necessary at the time, positively and proportionately IF you've never used much rudder that might present difficulties. Perhaps a tailwheel endorsement might help in those circumstances.  Nev

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Posted (edited)
29 minutes ago, RFguy said:

70 kts is too hot IMO for that config. Vflaps is only 84 kts.

Hi, I normally come in at 70 knots, and reducing to 65 knots, once I cross the runway threshold. 

Edited by anjum_jabiru
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Maybe practice some short strip approaches with your instructor . (landing on the keys and bringing it to a stop quick) 

 

 IMO that's a good exercise in improving approach technique.  my experience with that is that I  must fly a slow  and stabilized approach to put down on the keys and stop in minimum distance .

 

have a read in the J230 POH "4.10.2 Short Field Landing"

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Depends on your weight and the conditions (Gusts).  IF you are slow your flare will be more brief. If you tend to float you are a bit quick. Nev

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The Jab book is reasonable, IMO. I think the NOTES jab provided here are pretty well on the mark. 

any comment , others ?

short fields are worth practicing with instructor...

 

Clipboard01.gif

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1 hour ago, RFguy said:

The Jab book is reasonable, IMO. I think the NOTES jab provided here are pretty well on the mark. 

any comment , others ?

short fields are worth practicing with instructor...

 

Clipboard01.gifHaving read the notes attached to this post, I am further convinced to not fly a Jabiru. Why is a short field approach and landing any more risky than any other? 

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34 minutes ago, Roundsounds said:

Having read the notes attached to this post, I am further convinced to not fly a Jabiru. Why is a short field approach and landing any more risky than any other? 

Basically the POH says to drag it in, low and slow with power. The risk is if the engine quits, you've got no safety margin in airspeed or height.

Edited by RossK
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