Microlighters

Rob,

all my posts have been generic, but slanted towards the LSA. Look back over my last few posts to get all the detail

Thanks, Morph

I have compiled a list, based largely on yours and ignoring the obvious, like having to have an ASI and and altimeter. I think that I am accurate enough to pass any ramp inspection except for one or two minor issues like weight and balance data. I have gone through the CATS and CARS on the RAASA site, but nothing is listed there. I shall have to ask if anyone knows how a new aerie is affected by this. Ours is fourteen months old and came with no W@B info at all. I'll try the Cheetah forum to see what other owners have if there is no answer forthcoming,

Rod Smith

PS
May I also add my name to the list of people who have expressed appreciation for your work in this connection.

CAA should have a copy of the last W&B on your file. It only needs to be done every 5 years or if the plane has been though a rebuild or accident. Maybe they can fax you that page. Speak to Braam Hector at 011 545 1396

The previous owner should have it on record in the logbook as well. Otherwise you are going to have to have it reweighed.

Speak to the factory to get the spreadhsheet. I have a generic spreadsheet, but I don't have the details of the datum, ARM's (distances to the front and rear wheels, seats, fuel etc etc ) and the safe cg specification. If you can get those figures we can drop them into the spreadsheet

Morph,

could you please post the electronic form (word, oowriter, pdf, etc.) of the self-made flight-folio of yours from the post viewtopic.php?f=1&t=8280&st=0&sk=t&sd=a ... 90#p101290 in this thread?

Many thanks!

Cheers,

V.

Thanks, Morph

I shall try the factory and the CAA. I met Braam and Piet the other day when I went to effect the authority to Fly. They were helpful and pleasant in every way.

The Owners Manual gives the datum point and mentions that the forward and rear limits of the C of G are behind this point, but then supplies nothing else at all. There is also nothing in the log books and other material. But it is a new aircraft, at fourteen months, so the factoey should be able to help.

Rod

Thanks Morph for posting the folio doc!

Cheers,

V.

Thanks, Morph, from me too!

I spent a while yesterday constructing a Flight Folio page, only to wake up later to yours. Yours is much better in its construction. (I am still working on the C of G issue. Your page for thid looks good, as well.)

Rod Smith

Now the CAA has revoced the reocation of our mates ATF. On the grounds that the list is applicable to Type Certifieds only. Now WTF has all the fuss been about??

I have updated the weight and balance form to the exact one CAA accept. Fill in your weights and arm lengths. The manufacturer should be able to give you the acceptable C Of G range measurements

After a short flight with my Savannah this morning i was inspected by two caa manne,Piet Viviers and Danny Rost.

All went well exept for the certificate to release to service ,which i dont think is applicable to zu aircraft,and they were pleasant guys to meet.

Thanks to you guys for the info on this forum,it saved my ass.

Morph,
What is "arm length"?

Ou Man wrote:Morph,
What is "arm length"?

The manufacturer of the aircraft select a specific datum on the aircraft as reference point for the cog. Then all the weights is measured as "distance from datum". This is called the arm or arm length. From this the manufacturer will determine the safety envelope in which the aircraft will be loaded to be operated safely.

Hope this help.

Exactly,

the manufacturer defines the datum, i.e. a common point that is used as the starting point in all the measurements. In the case of the Bushbaby, you have to put it into a flying attitude, i.e. wing tips level. Drop a plumbline down from the leading edge of the wing and this is your datum. All measurements are done from this point

Positive values are behind (towards the back of the aircraft) and negative values are ahead (to the front) of this point

The ARM is the distance from this datum to the item being measured, usually the three wheels, then the fuel tanks, seating and luggage areas
The MOMENT is the weight X ARM length measured at these points of measurement.

You weigh the aircraft on all three wheels. If you only have one scale then the other 2 wheels need to be lifted up using blocks to ensure that the aircraft maintains this flying attitude. This is critical, even a slight angle will throw the measurements off.

Then you add the other weights. Fuel weighs about 0.71KG per liter

The manufacturer will give you the safe CG range, i.e. 268mm to 373mm aft of the datum for the Bush Baby.

Experiment with the max and minimum realistic loads, i.e. there will always be at least 1 person in the plane, and see that you remain safe. In other words work out a starting CofG with 1 person, full fuel, max luggage. Then work it out with minimum fuel as if you are at the end of a journey and check if you remain safe. The CG normally moves forward during a flight.

Next do the same at MAUW, i.e. including PAX etc.

As far as I am aware, the ATF of a non type is it's Release to Service