What is wrong with the jab?

[turboplanner]

Just going back to Yenn's point, the nosewheel jamming problem depends on who used the aircraft last and whether they fully extended the adjustable pedals, so the first you are aware of the problem is when thje nosewheel is locked at an angle and you are heading for an aircraft/the bush with only the Jab brakes to stop you.....I accept it is the PIC's responsibility to check this during the preflight, but the Jabiru fix solves the problem permanently.

 

 

[Guest wayland1]

Thanks yenn for your comment. I tried to bow out of the thread, getting the feed back I needed and not trying to make any enemies. In Kents defence I stand by my original concerns. (Sorry Captain) Kent actually has more hours on the Jab than I do. I have about fifteen but hold a full licence, xcountry etc. I am new to power and RA aircraft. My history is with gliding, around 1000 hours. I am 50 now, started flying at 17 became an assistant instructor at 19, went on to become a level two instructor and CFI. Was asked to become a level three, (instructing instructors) representing the NSW North Coast area but declined. Operated a Gliding adventure flight business from Coffs Airport for three years in the late nineties. Only primary control zone in the world at the time facilitating both gliders and skydivers. (according to Dick Smith) Please don't think I am blowing my own trumpet but it is the reason this issue concerns me so much. When I first flew the 170 Jab 5334 I accepted the fact that it was a dog (as somebody had mentioned), on the ground. My first landings had me horrified, literally from one side of the runway to another after touch down and trust me 21/ 03 at Coffs is fairly wide(fits a 737) eventually worked out that holding the nosewheel off as long as possible (as concluded) seemed to keep me away from the rouge shopping trolley syndrome. Trust me, landing on one wheel all of your life is a breeze by comparison providing the crosswind doesn't force you to drop a wing to early. I have flown gliders that need a cut lunch and half a days trek just to walk to the wingtip. (well maybe just morning tea) None of the GA pilots at Coffs want to fly the Jabiru, but thats GA pilots. (They think that the rudder pedals are purely used as a foot rest between landing and takeoff) and the jab needs tlc with the pedals in the air, like a glider. After recieving my licence with all of the bells and whistles. It was about 4 weeks before I flew again. When you are still a beginner ( I still consider myself that once more) a couple of weeks seems an eternity. I took my daughter for her first power flight with me. Normal flight, landed on one zero, the cross strip at Coffs, slight crosswind touched down. In hindsight, assumed, and rightly so, that I had forgotten the drill and presto, was heading to the left (always the left) at a great of knots. Was composed enough to hit the brakes with full opposite rudder and stopped short of running off the runway, of course to the scoffing of my 18 year old daughter who will never let me live it down. That concerned me for a long time. I certainly had not considered that I had done anything wrong, certainly did not think I had experienced some sort of post touchdown phsycoyic episode and held my foot firmly planted on the left rudder in an attempt to make an idiot of myself in front of my first power passenger. This situation had been foreign to me, however, so had flying an aircraft with a steerable nose wheel. I had done a couple of GA tifs in a 152 and never had to think of directional stability, taxying, taking off or landing, just wasn't an issue and I understand that GA aircraft are not RA aircraft. However I do understand, as somebody who has had the welfare and safety of pilots, student and experienced, firmly on my shoulders, albeit under the watchfull eye of CASA.

 

Now, our situation at Coffs Harbour is fairly critical, not just for the few of us who have pioneered the RA change at this airport (through the hard work of others) but for the future of RA generally as it gains acceptance (reluctantly) by the relevent bodies which hopefully this year will allow Ra pilots and Ra aircraft to fly into control zones like Coffs. We would certainly love to see all of you make it to Coffs when that happens. The beer will be free of course...courtesy of Kent.

 

I don't know what CASA will make of the incident with 5334. It took a lot of work to to convince CASA to draught an instrument allowing solo RA pilots to operate within Coffs class D airspace, a prelude to the freedoms you guys will be given in the near future, hopefully. (remember the beers free) perhaps everbody should take on board obvious issues with the Jabiru or whatever type Ra aircraft you fly. I certainly think there is one with the Jab. (the evidence shows) As somebody else said, some are great....some are not so great. I guess it's up to everybody to decide for themselves. Buy the way. I agree the jab is a tough bastard. Turned it over the other day, apart from the strobe( which has never worked...sorry Captain) being broken, there did not seem to be any other damage past the firewall. (some corrosive blood on the wing....thanks kent...you'll be buying top shelf buy the end of this) No signs of cracks in the gelcoat, so may not be to bad. Will suggest the front tyre type be looked at and other suggestions. Cheers Paul

 

 

[Guest wayland1]

No worries Geoff

 

 

[Guest Orion]

Hi All

 

Thanks for input and constructive comments except bloody wayland who seems intent on giving away all my beer.

 

Seriously though

 

For Ian

 

No wind at all cross or otherwise was perfect conditions.

 

Going over in mind suspect nosewheel down maybe a touch early but as pointed out in earlier comments its what happened after thats scarey.

 

Cheers

 

Kent

 

 

[Guest Orion]

Hey Guys

 

Just went and read the AD on the rudder pedals.

 

AD is issued for the J160. Doesn't mention J170 anywhere in the AD.

 

Can anyone enlighten ?

 

Cheers

 

Kent

 

 

[Guest brentc]

Yes, it's for both. The AD was put on the wall of our school and I noticed that someone wrote 170 on it by hand. From memory, only later 160's had the adjustable pedals as the early ones just had timber blocks, basic, but effective!

 

 

[Guest Orion]

Thanks Brent

 

But isn't that a problem.

 

The AD is issued in respect of the J160, can't see anything in the AD that mentions J170

 

If it applies to both then it should say so.

 

I spent 6 years as groundcrew in the RAAF in a much earlier life (much younger and with different wife)

 

From my recollection of those days maintenance directives were very specifically drafted to include all possibilites which saved technical ground crew second guessing what it applied to.

 

Cheers

 

Kent

 

 

[quentas]

When I picked up my 230 from Bundy just over a year ago, I went to Gladstone to visit relies before flying home to SA. There was a xwind of about 12 knots from the west on runway 10. Straight after touching down, the plane started to `slide` sideways on all 3 wheels with a shuddering throughout. I had the stick well to the right. I havnt had this happen since. My guess is it was an increase in the xwind at the time of touchdown. In a `GA` aircraft, you probably wouldnt be affected by changes in wind strength as much. My cessnas empty weight is over 600kg whereas my Jab is 360kg yet the Jab with four seats will carry more, faster and further than the 172. I guess my point would be an aircraft such as the Jabiru is a `high` performance aircraft even when compared to GA types, but the fact is they are much lighter and susceptible to variations in wind speeds compared to the heavier `tinnies`and have to be flown as such when near the ground. I would be interested to know how many other LSA type aircraft have departed the runway in similar conditions (mechanical faults excluded) cheers, Q.

 

 

[Guest ROM]

Jab LSA 55; Nice steady approach right down the centre line to our 30 metre wide sealed runway.

 

I had just started the flare when in literally a couple of seconds I found myself 10 metres off line still airborne and still pointing down the strip.

 

I didn't have a clue to what had happened as it was so fast.

 

My only guess is that I hit an invisible very small but intense willy willy which I have often seen starting on our large sealed strip while launching gliders.

 

Most pilots won't see these small willy willy's being generated by the heat of the black runway asphalt as pilots generally don't get near runways for more than a few minutes and don't sit around on runways for extended periods.

 

These small intense willy willy's can shake up much bigger aircraft let alone a small Jab.

 

 

[Yenn]

Qentas. What were you doing landing on 10 with a wind from the West, surely 28 would have been appropriate and with only 10 degrees of cross wind it would be negligible?

 

Rom, what you describe sounds to me like a good gust of crosswind, willy willy or otherwise, but usually if it is a willy willy the effect doesn't last long.

 

 

[quentas]

Oops, it was a direct xwind from the right which makes it pretty much a southerly at the time. Being an unfamilier airport, It takes me a while to get my `bearings` sorted. 10 was the `active` runway at the time. Thanks for picking that up.

 

 

[jcamp]

Unable to comment on 170 but the 160 has far more aerodynamic control on landing than the LSA etc. Bigger ailerons, rudder etc gives far more control and avoids that round out and become a passenger feeling.

 

 

[Guest Andys@coffs]

For consideration.....

 

Its unlikely that at Coffs there is a prickle problem given the acres of tarmac, however I'll comment on my own experiences.

 

On my J230 I have had a number of punctures, and spat problems. In almost all cases directional control on the ground was impared and the aircraft wanted to exit to the left or right and needed quick correction. I' go so far as to say that in general a very low time/ just solo pilot could easily find thenselves upside down. I dont think this is just a jabiru issue, any tricycle geared aircraft with one failed will create issues...

 

The worst case was the spat Aluminium U channel cracking which allowed the spat to rotate and lock the wheel on landing.... I guess it did show how short a landing could be made with really good brakes....

 

Recently, as a seperate issue, I had a flat nose wheel and found that I lost rudder authority quite quickly (sort of an extreme example of Bretts suggestion of the need for a round profile cross section... I had an inverse round cross section)

 

In my case, as has been suggested elsewhere, Im moving from 6 to 10 ply tires and I note (with embarasement) the need to RTFPOH as I wasnt inflating the tubes sufficiently, somehow I had it in mind that a lower pressure was needed.

 

Anyway.... may see you around shortly as Im about to move from Adelaide to Coffs Harbour, thinking of buying a farm west of the ranges so I can have some prickles to justify the purchase of the 10 ply tires....:big_grin: Looking forward to having a river as we in Adelaide are very close to forgetting what a healthy river looks like...

 

Andy

 

 

[Guest Orion]

Just to keep everyone in the picture.

 

Took a trip up to Grafton yesterday. Stu who runs the flying school up there sat in the right seat while i did a couple of circuits ( six i think to be exact).

 

apart from the first landing which was understandably a little tentative ( I lent on the left rudder a bit much just prior to touch down and he corrected it) the other five landings were good. Stu kept his hands and feet off the controls.

 

Only thing i did different was very conciously held the nosewheel off the ground for longer, happily when i put it down it stayed on the runway. Yippee !!!!!!!!!!!!!!

 

Interesting experience for me on a number of levels.

 

first up i think most of the taxiways at coffs are wider than the strip at South Grafton. Its certainly an experience making an approach on a strip narrower than your average driveway. Probably explains me being a bit tentative on my first landing without the added pressure of the aftermath of the last landing.

 

Secondly despite being the same aircraft type the rudder feel in the Jab in grafton is much different the aircraft tracked true along the ground.

 

Interesting the comments about the AD earlier, i checked with RAA as i was confused and point blank asked the question did the AD apply to a J170. answer is yes but not all.

 

Checked with the LAME responsible for the Jab i bent and he is adament it doesn't apply.

 

so in the end i'm still as confused about it as before.

 

Cheers

 

Kent:thumb_up::thumb_up::thumb_up:

 

 

[Guest brentc]

If the Jab that you had your incident in has the mechanically adjustable pedals, then I believe the AD will apply. As far as I know and I hope someone can intervene if I'm wrong, there are only 2 types of adjustable pedals on the Jab, the ones with the timber blocks and the latest adjustable metal ones with the sliding pieces and locking pins.

 

 

[Guest Orion]

Hi Brent the pedals were the same in both.

 

metal tube with pins.

 

no sign of a wooden block anywhere

 

cheers

 

kent

 

 

[Guest Macnoz]

Kent,

 

if on pulling out the pin you could have removed the pedal fully form its tube - the AD was not done- simple.

 

While it is not uncommon to have different"feel" in similar aircraft no more than cars,

 

remember the "ground" was also different -- and the wind and several other factors.

 

I just loved how others jumped in here to blame the craft straight up.

 

At least you didn't. You had after all undertaken several hours in it so it is highly unlikely that it reserved its demonic behaviour to surprise you on the first solo

 

 

[Guest Orion]

Hi Macnoz

 

Yep don't blame the aircraft.

 

All my flying has been in the Jabiru. I'm happy with the way its flies. Lets add in Takes off and lands here as well.

 

No complaints at all and you won't hear any from me.

 

However and its a big however. It handled like a pig on the ground.

 

As paul said in his original post he had difficulties and he has lots of experience. Paul wasn't the only one.

 

Yep my first solo but i did nothing wrong in the flight at all as i've said before on a couple of occasions.

 

The incident happened on the ground.

 

My axe and i'm going to grind it now is that the AD everyone refers to is issued on a J 160.

 

there is no mention at all of a J 170.

 

So when i approached the LAME about this his response was it doesn't apply. And legally he is right.

 

I spoke to RAA about the AD and point blank asked if it applied to the J 170 and the answer was yes but not to all. See Brents comments about different versions of the pedals.

 

I pointed out that the AD only addressed the J160, was a bit of silence at that point.

 

Think i'm vindicated as today a new AD and it addresses both J 160 & J 170 family and helpfully has diagrams of the rudder pedal assembly.

 

Same setup as was in the J 170 i had the incident in and the assembly was adjusted fully out so now it all makes sense. No AD done.

 

When the nosewheel came down and started to depart left i took corrective action with application of right rudder but malfunction per the description contained in the AD.

 

at least now i know or at least can be comfortable with the notion that i didn't cause the incident.

 

Kent

 

 

[tvaner]

Well done.

 

....I pointed out that the AD only addressed the J160, was a bit of silence at that point.

Think i'm vindicated as today a new AD and it addresses both J 160 & J 170 family and helpfully has diagrams of the rudder pedal assembly.

 

Same setup as was in the J 170 i had the incident in and the assembly was adjusted fully out so now it all makes sense. No AD done. When the nosewheel came down and started to depart left i took corrective action with application of right rudder but malfunction per the description contained in the AD.

 

at least now i know or at least can be comfortable with the notion that i didn't cause the incident.

 

Kent

 

Well done Kent.:thumb_up::thumb_up: There is no doubt that your determination to find out the true cause of your incident, and your willingness and courage to share it openly on this forum, has now had an impact on safety that we will all benefit from.

 

 

[Captain]

However and its a big however. It handled like a pig on the ground.

This point has been regularly mentioned by Orion and the Pres of the Club that runs the aircraft ...... so if this particular aircraft handled in this way and they observed its "pigishness" or were so concerned, I can't help asking why any Student or particularly a 1st Solo Student was permitted to operate it?

 

And I hasten to add that in my experience the 160/170 does not normally exhibit this trait, so perhaps something was out of adjustment or loose, yet it was still signed out for a 1st solo??

 

 

[Guest brentc]

Hey Keith, you fly the 120 don't you? Do you have any problems like this where the machine veers off the runway requiring some tricky evasive action?

 

 

[tvaner]

Hi Brent,

 

No, generally the J160 & sometimes the J170. (Haven't tried the 165!!! yet) But, with my long legs I don't need the peddles up.

 

(Have a few photos you may be interested in seeing though)

 

 

[Guest brentc]

I got confused. Was thinking that you owned a 120 (another Tooradin'ite does but it's not kept there).

 

For those that are wondering about the 165, it's essentially a 170 but for the purposes of billing, it's a 165 because it's a 170 but doesn't have the glass cockpit like the other 170's do.

 

 

[Guest wayland1]

Hey guy's don't mean to harp on the subject. 6'00 news Coffs Harbour. Old Bar airfield near Taree. Jabiru upside down. looks like a write off pilot (and passenger I think) injured Not sure of the details. Eyewitness report states the aircraft touched down, i assume normally then veered sharply off the runway and overturned. Further report stated that the cause seemed to be with the brakes, though the reporter probably didn't understand the workings of the aircraft...couldn't have been a problem with the rudder or nosewheel assembly could it.....no of course not.

 

 

[motzartmerv]

Thats no good.. Hope all are ok..

 

Tell Stuey that Andrew made it home in the gazelle, and thanx for havin me.. I forgot to leave $10 for him..Ill get him next time...

 

cheers