Jab SK MTOW

[Guest Escadrille]

Hi all,

 

Is the SK series MTOW still 430 kg or has it been officially uprated?

 

I am looking to buy a nice example of the SK at the moment and it seems the useful load may be marginal with an empty wt of 253 kg.

 

What are operators doing?

 

Cheers,

 

Escadrille:juggle:

 

 

[Guest Escadrille]

Thanks for that Brentc. So *everyone* knows that the aircraft can handle a higher load then..

 

So may I ask a ball park figure that evrey one is using then?? for example 20kg higher? i.e. up to 450 kg?. I realise any increase affects stall and take off length etc.. and realising the fuel load burns off as the flight progresses..

 

 

[Guest Escadrille]

Ok Its alright I have my answer now, Thank you. I know some questions can be a little contentious...

 

Andy

 

 

[Bruce Tuncks]

Sk mtow

 

There was an SK built in SA by Andy Hollitt, I'm pretty sure that his was extended to 480kg on the basis of calculations etc he submitted to the then AUF.

 

At one time I was intending to do the same thing, but with an empty weight of 240kg it wasn't urgent .

 

If anyone wants to know more about this, I reckon I can get in touch with Andy and check it out.

 

Bruce

 

 

[Guest Escadrille]

Hi Bruce, Well yes if there is any supportive evidence there I would be very interested to hear from Andy. thanks very much Bruce,

 

Regards,

 

Andy

 

 

[Bruce Tuncks]

sk mtow

 

Well I've finally got in touch with Andy Hollitt, and yes he did get his SK weight up to 480kg.

 

He was able to do this because the 430kg limit was based on 40kts stall speed, and when the stall speed was increased to 45 kts, a simple calculation will show that the corresponding weight is well over 480 kg.

 

There may be a bit more to the story, I'm getting a copy of the correspondence.

 

cheers, Bruce

 

 

[Guest Escadrille]

Makes sense.. Many thanks Bruce. I will wait to hear further.

 

Andy

 

 

[Bruce Tuncks]

SK weight

 

Hi Andy,

 

Yes the info I got verbally was correct, and Andy Hollit has sent me a copy of the correspondence. The Jabiru was initially certified at 430 kg and 40 kts stall. Now, as Brentc correctly points out, changing this would cost a lot. BUT with a kit built the regulations are different, it was never certified anyway and the builder was the manufacturer.

 

Well Andy Hollit showed that 430 kg and 40 kt stall converts to 544kg and 45 kt stall, while asking for an extension to 480 kg. This was approved by the then AUF (R.Hewitt-Cook ).

 

So there is no technical reason why an SK cannot proceed to be approved at 480kg, especially as we know that the airframe is as strong as a brick dunny.

 

If you email me at [email protected] I'll forward you a copy of the correspondence.

 

Bruce

 

 

[diablo]

Jabiru sk mtow

 

Hi Andrew,

 

I have a Jabiru SK at Rayne (north of London). I got your details from the Jabiru UK website and was wondering if you could forward me your copy of the documentation that you submitted to upgrade the MTOW of your Jabiru SK.

 

I would also like to know if you could supply the aluminium cups or technical drawings with measurements you made for the rubber mounts as I need a set for my AC.

 

Much appreciated and thanks

 

regards

 

Dean Licheri