Quoted landing and take off distances for RAA aircraft - Specifically Jabiru 230d advertise these distances. Are they right at MTOW

[SSCBD]

I have not flown specifically a Jabiru 230d but looking to fly one in the next couple months with view to buying.

However I flown have many other types in RAA aircraft and GA.

I am interested in the quoted take-off performance of the 230d fully loaded at MTOW 600kg.

Jabiru advertise these distances.

Jab 230d take-off roll - 236 m

To 50ft  - 356 m

Landing roll - 140.5 m (love the .5m)

From 50 ft is -  534.5m (again .5m really)

I assume this was done with nil wind, on tar and at close to sea level and at MTOW? (I hope)

 

Question - And yes I know wind temp will make a big difference, but SAY in zero wind -  on grass but say 30c how much extra will it affect the 230d fully loaded?

Anyone with experience with the 230d performance please comment below.

Also are they about right or not about the quoted distances to start with.

[skippydiesel]

Soooo tempted to encourage your interest elsewhere BUT you do seem focused on the Jabiru J230d so will leave well alone.

[Bruce Tuncks]

Well I reckon your aircraft choice is fine. And there is a lot of regulation surrounding those figures. There is a set of CASA directions defining weights etc.

I can say with certainty that the figures would be at legal MTOW.  The atmospheric conditions would also be specified but I didnt see them on a quick look. My guess is that they would be for a "standard atmosphere" and you should de-rate the figures for hot and high.

Not relevant, but once I watched a 2.2 Jabiru take off in company with a Cessna GA plane. The Jabiru was a good hundred feet higher before they reached the cross-strip. There was no comparison between them regarding take-off distances, the Jabiru was so much better.

[mkennard]

For the landing roll, be careful with your approach speeds. It is so easy to float the J230 though once on the ground it doesn't need much distance. 

[Jim McDowall]

Figures from 230 POH

Note figures are for paved surface at MTOW, 100' at 24 degrees C. Performance can degrade quickly at higher airstrips in the heat.

Google "Koch chart" for an interactive nomagraph to calculate performance at various heights and temps.

[mkennard]

Someone created this once. Remember it's not an official chart.

J430 TO dist chart estimator.pdf

[Jase T]

Also remember the stated figures are for a factory new aircraft, with a factory new engine / prop. Not one with dents and faded paint and bugs and 1500 hours on the engine...

[skippydiesel]

1 hour ago, Jase T said:

Also remember the stated figures are for a factory new aircraft, with a factory new engine / prop. Not one with dents and faded paint and bugs and 1500 hours on the engine...

Ooooh! Jase - go carefully - sounds like my cautionary comment, several back - you might end up being burnt at the stake

[old man emu]

These performance figures always beg the question - can they be achieved by the pilot who does not fly on an almost daily basis, or are they produced by a pilot who gets a couple of hours over the course of a week's employment?

 

What fudge factor would you think reasonable to add to the published figures to account for real world operations?

[skippydiesel]

26 minutes ago, old man emu said:

These performance figures always beg the question - can they be achieved by the pilot who does not fly on an almost daily basis, or are they produced by a pilot who gets a couple of hours over the course of a week's employment?

 

What fudge factor would you think reasonable to add to the published figures to account for real world operations?

OME - I dont think this is  a figure that can be easily quantified or fixed. Too many variables!  - Aircraft load, X wind, cleanliness of aerofoils, pilot skill, familiarity with that aircraft, temperature & altitude. etc . The pilot must make his/her own determination of what the aircrafts performance might be on a given day and apply the "fudge" factor that they think they can "live" with.

[RFguy]

Note the point  in the POH :  
"The distances quoted above are for the following typical scenario:"

and 

- "An aircraft at 600kg and forward CG position,"

 

Forward CG position in this aircraft, for me would represent 2 x PAX plus 100 litres fuel.
*this is the forward CG scenario they are probably talking about- this is the usual scenario with not much in the back.*
150kg PAX + 75kg ish of fuel  is MAC = 16.6%. It can go to 28%
Note the stall speed reduces slightly with CG moving aft, so with alot of stuff in the back, it might start flying earlier (but the 50' numbers might not be all that different depending) 

Jabiru numbers are usually conservative, and account for variations across aircraft. I would guess that this is for the worst case for a new aircraft .
Mine gets off the ground like a scalded cat. But it is all relative....
 

 

Edited January 18, 2021 by RFguy

[SplitS]

What matters a lot is what the approach and departure look like even though overlays allow for "angles" off the end of the runways it makes an big difference in reality between coming in over crops or gum trees, power lines etc. I love the Jab's but would not consider flying one off a 300m strip.

I also love my Subaru but for a Simpson desert crossing I would use my Land cruiser. Sometimes you have to choose the right tool for the job.

[facthunter]

The "THING" that will GET you is density altitude  (hot and high) and non level (sloping),  and grassed/soft /boggy strips. With a forward CofG, the extra download on the tail has the same effect on the wings as adding that weight to your AUW.. Nev

[RFguy]

As a fairly inexperienced J230 pilot, I would say :

1) Making takeoff distances is easy. Any mug can do that. 

2) Making those landing minimum distances- much harder ! much practice required !