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Guest wayland1

What is wrong with the jab?

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Guest wayland1

Hey guys Time to give some input. Just got back from the airport (Coffs Harbour) had our Jabiru flip after veering to the left after touchdown, first solo flight minor injuries, major damage. This is becoming a familiar tale with this type of aircraft. I have experienced the same thing. Although we have had trouble with the main wheels not tracking correctly, I have always put the veering problem down to the nosewheel. Hold it off after touchdown as long as possible and it doesn't seem to be a problem. Drop it to early and it seems to be like a runaway shopping trolley. Perhaps the pilot added to the effect in the confusion. If so, that is quite understandable considering the flight was a first solo. I don't know what the home built Jabiru is like considering the TLC that goes with it But I have not got a good word to say about this aircraft or the companies attitute (according to our LAME) Example. Flap actuator faulty. Replaced under warranty. Company sends a second hand unusable replacement, thread completely stripped off worm drive. Had to send it back to have a new one returned. Believe it or not...put it in yesterday.....can't say I am not XXXXed off!!! any comments. 036_faint.gif.544c913aae3989c0f13fd9d3b82e4e2c.gif

 

 

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they are CHEAP! and hence, selling thousands! i have flown numerous types of Jabs, some fly brilliantly, some are dogs, seams to be luck of the draw on how its put together. fortunately i have not had a veering problem with the jabs, but it could be down to simple wheel alignment, at the fatory, the parts come together, and get bolted to th airframe, thats it. so a little aligning after you get it home will make a world of difference if its out a bit. funnily enough, our early LSA fly very well, and we are very happy with them, even after 5000 hrs! yet some of the newer built ones, well, i have heard a few horror stories around the traps, mainly with the J160 though.

 

Our main training jab LSA, has No wheel spats, no U/C fairings old square front cowl, and cruises at a genuine 100kts at 2800. yet another LSA we cross hire, has spats, had U/C fairing, rounded cowl, hidden air intakes, and will only do 90 kts at 2800, and will always drop a wing when it stalls, and it stalls 4 kts faster than the rougher one.

 

The main and only problem with Jabirus is they are built to a price, and a very cheap one at that! where else will you get a 2/4 seat aircraft, that will cruise at 120Kts carry 135 ltr of fuel with a range of 800NM, for under $100K Brand new. for that kind of money, a bulletproof reliable airframe, you can overlook their rough points.

 

personally, i think they are as Ugly as Hell. yet love them for what they can do at such a low price.

 

 

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Guest wayland1

The model is a 170c. Don't get me wrong. I want to love this aircraft. It's great looking. if you want to get newcomers into ra aircraft, this is it. I like to fly it, it is roomy for its size but it has been a constant visitor to the l.a.m.e from the time it arrived ,brand new and as President of my aero club I could never confidently buy another... 90 odd thousand dollars for an lsa aircraft, I don't treat as a cheap buy. This accident could have been a lot worse.

 

 

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Yes, could have but wasn't.. The jabs are as tough as they come. They have been spun in from 100 feet and pilots walked away and acft flying again..

 

First solo and running off the runway, sounds to me like perhaps a bit to soon jumping out and sending the guy??... They are difficult to stear on the ground, i thought the 170 was better then other models though..

 

cheers

 

 

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wayland1

 

My experience has been exactly the opposite of yours .... although mine is a 230 from a kit .... but I make the following comments:

 

1 If the nose wheel goes down on landing with a heap of rudder kicked on then it must be a bit of an issue as the nose wheel will be turned. Holding the nosewheel off and neutralising the rudder as it goes down removes all issues (for me).

 

2 I have done a reasonable number of take-offs and landings in a 160 and have never found tracking at speed to be an issue of concern.

 

3 I believe that the 10 ply Trelleborgs have a less rounded crown and give better tracking than the 6 plys (in my experience with them on a 160 & 230) so may be worth a try.

 

4 The service that I have had down here from the Jabiru factory has been exemplary during and after the build. Any items are sent immediately, sometimes within hours to make that evening's shipments, and have always been exactly what was asked for.

 

5 Surely you don't think that they sent you a 2nd hand stripped actuator on purpose to rip you off? I would suggest that someone up there just sent the wrong one in error .... hardly a hanging offence.

 

Hope this helps and try not to blame the aircraft manufacturer each time a 1st solo student has a whoopsie or you'll be doing it a fair bit.

 

Sounds like your LAME is on a good thing with you and your Club. There are many 160 and 170 owners on this forum who have not had the same experience as you ... & I hope that they post to your thread ... and I know of a number in schools where the experience has been good to excellent. So what's the difference?

 

Regards Geoff

 

 

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I have never flown the 170, thats the model i am thinking of purchasing if i cant get a 230 cheap enough.

 

What were the tyre pressures like?

 

 

  • Informative 1

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Bit more information needed. Was there a crosswind?

 

Was he landing nose up?, down? I've found the J170 wing very sensitive in cooler weather (remember it was designed for hot take off performance in northern Australia).

 

 

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Guest ROM

One of our guys, a very careful and very switched on type of guy, had a lot of trouble with his own kit built J230 when landing as he claimed it also was inclined to depart for the scrub after touch down to the extent that he got a bit wary of flying the aircraft.

 

He did a complete rework of the main wheels both in camber and toe in and now claims to have fixed the problem with the aircraft tracking true down the strip after touchdown.

 

The owner kit builder of the J170 has a similar curved leg set up to the J230 but does not seem to have had any problems as his aircraft lands and tracks straight and true.

 

The Jab main under carriage legs vary between models with the early small 55's having straight legs angled forward.

 

The J120 again has straight legs but they are almost vertical and we don't seem to have any problems with it after landing.

 

The J 230's and J 160/ 170's have a nearly 90 degree radius bend in their legs from the fuselage to the wheels.

 

Being glass this particular design possibly has some very interesting dynamics as it can rapidly flex back and forwards and at the same time develop some twisting as well as changing wheel camber as the legs spread apart and spring back.

 

All of which makes for some interesting wheel dynamics after touchdown unless the wheels are set up at the sweet spot for the dynamics involved.

 

 

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There is nothing wrong with a jabiru aircraft, you either love them or hate them, if you hate them then don't fly one or buy one, they are an excellent plane for the money that they cost and the factory has always been helpful in any questions, parts required or for help when needed when we built our J160. The man in Bundaberg when he designed this aircraft has done an excellent job in allowing an affordable aircraft to be available to everyone, just because they might fly different to some other planes does not mean that they are a problem, people hear about things going wrong sometimes as they do with all aircraft, its just that there are more of them flying around so the number of times something may happen is increased compared to other aircraft. The main problems for Jabiru is the lack of maintenance that happens or people babying their engines and causing problems and then blaming the aircraft for being a bad thing. They are one tough bird and we are happy to own one!

 

Brian

 

 

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Guest brentc

The problem is the 'square' nose wheel which is the standard 13x5x6 tyre as supplied by Jabiru. Lowering the nose wheel at high speed is like riding on the back of a poddy-calf (flipping back and forth over the backbone if you know what that is like).

 

Solution - change the nose wheel tyre to a 'round' type.

 

Solution 2, FLARE the aircraft and hold off the nose wheel. If it's held off for as long as possible then it will be near impossible to lose control.

 

Solution 3, ensure that the student is ready to go for their first solo.

 

BTW, companies can mistakes and send out an incorrect component! Our LAME has no complaints so it's really just a personal opinion I guess.

 

PS: The J170 does have a tendency to land nose wheel first if not flared correctly (as in not flared enough or long enough) so this nosewheel behaviour is usually experienced when moving from a 160 to a 170. I suspect the approach angle is different as the angle of incidence of the wings appears to vary between the two models.

 

 

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Guys

 

I'm the pilot involved. Was surfing the web looking for answers or at least information.

 

First thing i came accross was Paul's posting.

 

So in the interests of clarity lets get the facts straight.

 

Weather conditions fine, no wind at all, temp approx 24 degrees.

 

Had just completed approx hour of circuits, bringing my total flying time all in type to approx 26hrs.

 

CFI offered solo and i replied yes i'm ready. Dropped him off by side of strip at Alpha Taxiway. Tower cleared for takeoff. Took off and performed circuit perferctly, probably the best i have ever flown.

 

Glide, decent, round out and touchdown were all good. Touchdown was very smooth and gentle. Problem started moment that nosewheel touched runway, aircraft veered hard left, power was completely off at this stage, i kicked in right rudder to no effect aircraft detarted runway onto grass verge accross alpha taxiway and onto the grass beyond, we (me and the Jab) hit a drainage ditch and ended upside down.

 

Not a good look but fortuneately no real damage to me some cuts and bruises and damaged pride. Jabiru on other hand took a bit of a beating.

 

So question remains Why.

 

I have Reflected on this all day and probably will for some time to come. I'm a firm believer in learning from experience, my desire to continue flying is undiminished in fact had another aircraft been available i would have gone straight back up. So its important that lessons are learned.

 

Did i go solo too early, answer is emphatically no. I had done 26 hours most in circuit, I hadn't put any pressure on CFI to solo from the start i made it clear to him that I'd wait until he decided the time was right. The CFI has a vast level of experience so if he said it was time it was time. In anycase the Solo was as perfect as i was able to do from take off to touchdown it was spot on.

 

I'm 45 years of age with 5 kids i'm a bit past the bravado stage so i don't accept pilot error as a major contributing factor.

 

When the aircraft veered left and corrective action being application of right rudder failed to regain directional control then, with the benefit of hindsight, application of brakes may have slowed the aircraft better. In this situation everything is happening at once and probably as i was attempting to regain directional control i may have neglected to apply sufficient brakes.

 

Bear in mind you are sitting in the left seat grasping the controls with your right hand the brakes being in front of the controls to apply them you need to either let go of the controls with your right hand or let go of the throttle with your left and and reach over and apply the brakes ( bear in mind you have left hand covering throttle, read pulling throttle to make sure power is off at this stage) All this while the aircraft is lurching about the runway. Easy from the safety of a computer terminal much harder when it happens.

 

Seems to me that when you apply right rudder that the aircraft should go right, in this situation it didn't, Tells me something else was astray. Interesting in other places in this forum there is a discussion of a CFI with many thousands of hours who was trapped the same way and also off to the left.

 

Another forum i read talks about difficulties when feet are rested on pedals with feet off the floor as opposed to heals on the floor. This theory suggests a different pushing action one being pedals push forward (heals on floor) the other being pedals push down (heals off floor) The suggestion being one method can cause rudder pedal problems.

 

Happy to have me and my incident discussed, anything i can learn from this can only make me a better pilot and hopefully help others.

 

One things for certain................ My first solo was memorable.:thumb_up:

 

 

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When the aircraft veered left and corrective action being application of right rudder failed to regain directional control

sounds to me like there is an issue with the nose wheel, maybe a structural failure, i had a similar incident in my vampire, where upon touchdown, the link rod between the rudder pedals and the nose wheel failed, allowing the nose-wheel to spin freely shopping trolley style, and the aircraft departed stage left at about 30 kts, and rolled to a stop in the grass beside the strip. sounds like a similar thing has happened to you, another possibility is the tyre deflated, either in flight, or upon touchdown. either way, a good inspection of the nose-wheel and steering is in order. dont discount the possibility of FOD either, carpet or other object jamming up behind the rudder pedals themselves? water bottles are renowned for finding such hiding places.

 

 

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Guest Brett Campany

Cheers for coming here Orion and telling us what happened.

 

My TIF just a couple of months ago was in a Jab 240 and on take off we ended up in the scrub. We were very lucky!

 

I remember taking over on RW25, throttle up, kicked in right rudder but she still went left, no matter what I did she kept going left. I reckon if the Jab had differential braking we would've avoided the scrub but this bloody dual wheel hand brake crap needs to go! (that's just my 2c on that)

 

Mate even with power off I reckon there's no other way it would've turned out.

 

Hence the reason why I'm now doing my certification in a Sportcruiser.

 

Good to see you came out with just a few scratches.

 

 

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The one thing I can't understand and I don't fly in a Jab so it is purely opinion why on earth don't the manufacturers fit toe brakes on LSA's. To me the idea of having a hand/parking brake in the centre of the dash just seems dumb. I know of go karts with better breaking systems. I know it might add cost but hey surely following the design of other aircraft that have worked for years can't be a bad thing.

 

I have to admit MM comment about maybe solo was to soon was a bit left based considering nearly every thread on Jabs and nearly all accident reports seem to be a loss of directional control on landing-seems a trend to me. If owners can get their plane with an issue and then rectify it how about Mr Jabiru have a think about putting just that little bit of extra work and iron out re-accuring issues on future models.

 

 

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Are you a short or tall person??..were the pedals pushed right in and not in there most extended position. There was an AD brought out recently to stop the pedals being moved to the full out position. What can happen is the pedal opposite to the one pushed in comes out and the turning motion of that pedal forces it downwards towards the floor. Then when you try to correct by pushing that pedal you are only pushing it towards the floor and not the firewall. This problem combined with the jabs snakey landing roll charactaristics has been the cause of many of these incidents in ther past. Jabiru were very slow in bringing this ad out.. We reported the problem over a year ago.

 

Glad to see your ok and looking to learn from this misshap. Thanx for the open post, as you say it will help others in the future...

 

cheers..

 

 

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Guest pelorus32
Guys

I'm the pilot involved. Was surfing the web looking for answers or at least information.

 

First thing i came accross was Paul's posting.

 

So in the interests of clarity lets get the facts straight.

 

Weather conditions fine, no wind at all, temp approx 24 degrees.

 

Had just completed approx hour of circuits, bringing my total flying time all in type to approx 26hrs.

 

CFI offered solo and i replied yes i'm ready. Dropped him off by side of strip at Alpha Taxiway. Tower cleared for takeoff. Took off and performed circuit perferctly, probably the best i have ever flown.

 

Glide, decent, round out and touchdown were all good. Touchdown was very smooth and gentle. Problem started moment that nosewheel touched runway, aircraft veered hard left, power was completely off at this stage, i kicked in right rudder to no effect aircraft detarted runway onto grass verge accross alpha taxiway and onto the grass beyond, we (me and the Jab) hit a drainage ditch and ended upside down.

 

Not a good look but fortuneately no real damage to me some cuts and bruises and damaged pride. Jabiru on other hand took a bit of a beating.

 

So question remains Why.

 

I have Reflected on this all day and probably will for some time to come. I'm a firm believer in learning from experience, my desire to continue flying is undiminished in fact had another aircraft been available i would have gone straight back up. So its important that lessons are learned.

 

Did i go solo too early, answer is emphatically no. I had done 26 hours most in circuit, I hadn't put any pressure on CFI to solo from the start i made it clear to him that I'd wait until he decided the time was right. The CFI has a vast level of experience so if he said it was time it was time. In anycase the Solo was as perfect as i was able to do from take off to touchdown it was spot on.

 

I'm 45 years of age with 5 kids i'm a bit past the bravado stage so i don't accept pilot error as a major contributing factor.

 

When the aircraft veered left and corrective action being application of right rudder failed to regain directional control then, with the benefit of hindsight, application of brakes may have slowed the aircraft better. In this situation everything is happening at once and probably as i was attempting to regain directional control i may have neglected to apply sufficient brakes.

 

Bear in mind you are sitting in the left seat grasping the controls with your right hand the brakes being in front of the controls to apply them you need to either let go of the controls with your right hand or let go of the throttle with your left and and reach over and apply the brakes ( bear in mind you have left hand covering throttle, read pulling throttle to make sure power is off at this stage) All this while the aircraft is lurching about the runway. Easy from the safety of a computer terminal much harder when it happens.

 

Seems to me that when you apply right rudder that the aircraft should go right, in this situation it didn't, Tells me something else was astray. Interesting in other places in this forum there is a discussion of a CFI with many thousands of hours who was trapped the same way and also off to the left.

 

Another forum i read talks about difficulties when feet are rested on pedals with feet off the floor as opposed to heals on the floor. This theory suggests a different pushing action one being pedals push forward (heals on floor) the other being pedals push down (heals off floor) The suggestion being one method can cause rudder pedal problems.

 

Happy to have me and my incident discussed, anything i can learn from this can only make me a better pilot and hopefully help others.

 

One things for certain................ My first solo was memorable.:thumb_up:

G'day Orion,

 

No doubt you have had a tough day. Welcome to the forums and congratulations for your honesty and up frontness.

 

The only two things I would say are these:

 

  • Sit down with your CFI (if you haven't already) and go through the whole thing whilst it's nice and fresh. Understand all of the things that you did second by second and analyse them with the CFI - he/she is best placed to work this through. Tell us what you come up with;
     
  • I note you say "I'm 45 years of age with 5 kids i'm a bit past the bravado stage so i don't accept pilot error as a major contributing factor." I'm not able to judge what went on here so my comment is not about this incident. However I see nothing that relates being 45 and having 5 kids with an immunity to pilot error. I say that as someone a bit older but with fewer kids: I am always open to the though that I can stuff up - that approach is protective in itself.
     

 

Hope we see more of you in the future and best of luck getting back in the saddle.

 

Others on this forum will tell you that I am banned from saying anything about Jabirus 024_cool.gif.7a88a3168ebd868f5549631161e2b369.gif

 

Kind regards

 

Mike

 

 

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Thanks for the comments.

 

I'm approx 170cms about 5ft 7 in the old scale.

 

Will "ponder" the comments about the position of the rudder pedals. Assume what you mean is that if one pedal fully depressed opposite pedal affected interesting !!!!

 

For Mike

 

My reference to a bit past the bravado stage was a refernce purely to my readiness to solo. I've been around the block enough times to know my limitations. With flying its obvious pretty quickly that once its in the air it has to return to earth. If your the only one in the plane then its your job. Only a fool would B****it to themself that they were ready for that when they weren't. I accept the comments about pilot error a healthy respect for and acceptance of the fact that you can and do / will make errors makes you a more careful and not just as a pilot

 

Cheers

 

Kent.

 

 

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If anyone is unhappy with there Jabiru's i will kindly take them off there hands for a fee ;). Glad you are ok, Just make sure you learn from a mistake ? Wether it be yours or someone else's.

 

 

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Oh and for what it is worth, i find all Jabiru's i have flown very touchy on landing. On takeoff i make sure i feed power on until i am rolling straight then give her all the herbs. Just my personal observation.

 

 

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Kent, congratulations on your memorable first solo! Good to hear that no one was injured.

 

Having just gone solo myself this week, I understand the concentration and exhilaration that one is feeling as they touch down. The last thing a first time solo student would expect is something like what happened. Sure, you prepare for certain emergencies like engine failures on take off and in the pattern, but losing directional control on the roll out(whether that be a mechanical fault or not) is just not in the fore front of your mind.

 

I fly in the Sportstar and it's fitted with differential toe brakes. I've had vaguely similar things happen when landing in a crosswind due to not having the rudder centered when the nose wheel touched down. Similarly, if my crosswind correction was off, i.e. landing slightly crabbed, the Sportstar will also veer abrubtly, but never to the extent that directional control is not regained in a second.

 

Anyway, good luck with the rest of your training!

 

 

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I have seen smaller nose wheels fitted to the 160/230 and this has greatly improved the tracking on touch down.why you may ask? I dont know but my CFI always complained about the large front wheels on these models and when reduced made them easier to control.I would have thought it would be the other way around.Can anyone explaine that one.

 

 

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Guest wayland1

Thankyou gentlemen for your feedback. That is what makes these forums such a usefull tool. I know I have fired up opinions both pro and con but I have been able to paint a better picture of the whole situation, something that pondering on one's own can never really achieve. I still believe the problem with the on ground control needs to be addressed by the company and not just users individually. I you are experienced enough to be aware of what may happen on touchdown that's fine, but new pilots quite often can find the things we do quite unconsiosly a major part of the workload. Word has it that a number of training organizations are opting out of the Jabs for training. Perhaps there is a valid reason for that. I am begining to think I agree. Anyhow, I am glad Kent found this forum and told his story. Ask him how many beers he is up for. :thumb_up: Hope I haven't upset to many Jabiru lovers, but I think the subject is important and this is a great place to discuss it openly...cheers :big_grin:

 

 

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Word has it that a number of training organizations are opting out of the Jabs for training.

Care to enlighten us on which ones, or are you just going to leave it there with inuendo & no facts?

 

 

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