The Fleabike

[kgwilson]

The process is simple.

1. Apply for a Rego number in the category you have built . e.g 95.10, 95.55 etc. Then you can get the number issued printed & stuck on or painted on the aircraft.
2. Apply for registration. This must be accompanied by the Weight and balance data sheets, Aircraft Data Sheet and the signed off pre-flight inspection & the fee paid.
3. You will then be issued with an interim permit to fly. This allows test flights within 25NM of the home aerodrome without passengers.
4. After the required 25 or 40 hours apply for an ongoing permit to fly. You need to supply a certified copy of the test flight log & aircraft maintenance log and any mods or adjustments made. The certifyer is you if you are the builder.

All done. It is all in the tech manual.

[FlyBoy1960]

You are missing the inspection of the aircraft step, It HAS to be inspected by L2 or a CASA appointed person, then issued with a CofA, THEN you can fly

[spacesailor]

Item 1 completed .

Item 2 Refused by L2 on the grounds. ' Non-compliance '.

ssss

He knew what had happened, (  must have had communication ).

spacesailor

 

[kgwilson]

Nope. See item 2. The pre flight inspection has to be signed off by a L4 not an L2. An L4 can be a fully registered CASA LAME who registers and pays the RA-Aus L4 fee. The pre flight inspection was carried out by me, the builder, and checked by my L4. In my case my LAME hadn't paid the RA-Aus fee so I paid it for him which was part of our deal & was deducted from his fee. It isn't known as a C of A for RA aircraft. Previously an L2 could get special permission from the Tech Manager to perform this task if no L4 was available but this exemption has been revoked.

 

Section 3.3 of the RA-Aus technical manual Issue 4.1 dated March 2021.

 

3.3 PRE-FLIGHT FINAL INSPECTION An RAAus L4 Amateur Built Inspector must supervise the owner’s thorough inspection of the aircraft prior to applying for a Permit to Fly. This inspection will include a basic review of the weighing and weight & balance calculations for the Centre of Gravity (CG) limits, general appearance and quality of construction, compliance with all current and relevant Advisory Circulars, kit manufacturer’s Service Bulletins and any RAAus Airworthiness Notices (ANs). The builder is required to check off all the applicable items listed in TECH FORM 007 - PRE FLIGHT FINAL INSPECTION

[kasper]

Sorry all but you are out of date with inspections and out of touch with 95.10 which is different. 
 

both 55 and 10 have 4 inspections since the last tech manual. 
 

10 does not have the same permits and test flying.  It’s just registered and away you go. 
 

and whilst an inspection is standard L4 any L2 can be specifically authorised to do an inspection- that can be for. A specific single airframe or all of a type of aircraft depending on what the tech manager is feeling like allowing and what is asked for. 
 

basic rule - talk to tech office and all the mish mash of out of date and cross type discussions disappear 

[kgwilson]

Agreed that the 3 build stage inspections are now mandatory but these can be carried out by an L1 like me as I have previously built an aircraft (or an L2) but there is no exemption for a L2 for the final inspection any more.

[skippydiesel]

12 hours ago, kasper said:

................................................

 

people are not used to recovering fabric wings every 10years or so and maybe should - you still want to go in and take a look................................................................

.........................................

I refurbished my fabric covered wings about 5 years ago now. At the time, the aircraft was 13 years old.

 

Before removing the fabric I wanted to get some idea of its "integrity" - so using a Philips head screwdriver I attempered to punch a hole in it - my best attempt managed a permeant deformation (deep dimple). I was astonished that 13 year old fabric would be so strong.

 

I proceeded with the removal of the fabric - careful sue of a heat gun & considerable force was required - I began to question the need to replace the fabric.

 

Every surface was the same BUT ONE. 

 

One flap covering just came away without heat or significant effort - the glue seemed to have a different characteristic to all other areas. Whew! I would not have wanted that to happen in flight.

 

Using the Stewart System (certified) I replaced all fabric, increasing (above factory original) the surface area of glued contact.

 

Conclusion:

 

Although the integrity of most of the surfaces was excellent the failure of one might have been disastrous

Using modern fabric, adhesives, fabric UV treatments & paint combined with a more conservative glued area than original should see my fabric last indefinitely (I would still suggest close inspection/testing every 10 years)

 

 

[spacesailor]

See !.

Not every one here agree,s to what Should be the correct interpretation of those mirid confusing rules.

spacesailor

[duncan_rtfm]

Gave RAAus a call this morning.  Office directed me to Tech Documents, section 3.1  All seems pretty clear.  Then I went to join as a non-flying member, but the website wouldn't accept my application because I needed to supply a doctor's certificate to prove that I am fit to drive a car.  This, for a non-flying member.  Seems odd...

[Marty_d]

24 minutes ago, duncan_rtfm said:

Gave RAAus a call this morning.  Office directed me to Tech Documents, section 3.1  All seems pretty clear.  Then I went to join as a non-flying member, but the website wouldn't accept my application because I needed to supply a doctor's certificate to prove that I am fit to drive a car.  This, for a non-flying member.  Seems odd...

Something wrong there.  I joined last year as a non-flying member (hopefully that will change in a couple of years) and there was no mention of a doctor's certificate.

[kasper]

The website is a pretty horrid mess that RAAus know they need to fix. 

 

I'll start sounding like a broken record.  Call RAAus and ask for membership and they can do it over the phone.  No doctor cert required and you can get on with building. 

[spacesailor]

Non flyinb member! 

Does that mean your Not going to try & get your certificate, before you Finnish your plane ?.

spacesailor

[kgwilson]

There is no point paying extra to be a flying member if you are not flying. He already has a PPL so it is just a conversion with 5 hours when he is ready.

[spacesailor]

That, makes sense. 

spacesailor

 

[duncan_rtfm]

After a rather disastrous laptop infection by a virus which encrypted every file on my backup drive (thank goodness it wasn't my C drive) I finally found time to get back into the workshop and progress my wing.

 

My wings are constructed in three panels on each side.  Each panel hinges.  Panel A is fixed, Panel B hinges upwards, and panels C/D hinges downwards, allowing the entire rear wing (5.75m span) to fold into a 2m wide "concertina"

 

This is Panel A.  Each rib sits in a cradle, ensuring there is no twist, the ribs are perfectly spaced and sit at 90 deg.

 

The main spar consists of two 19mm x 19mm Hoop Pine spar caps, with a 4mm gap between them.  This is to allow space for the (discontinuous) shear webs to be bonded in place between them.

I know this is somewhat unusual - to have a discontinuous shear web - but I've had the numbers crunched, and the 9mm gap between each shear web segment is fine.

 

Here's a close-up of the spar caps.

 

Using West System with some adhesive filler, I bonded the spars in place on both panel A and panel B.  Once satisfied that everything was true, and that every rib was at 90 deg, I weighed the spar caps down with my trusty bricks.

 

 

By tomorrow morning, I should be able to flip the two panels, and bond the bottom spar caps in place.  If I get an early start (and if it's not too cold) I might be able to start sanding the spar caps to the contours of the ribs.

 

Regards,

Duncan

 

[duncan_rtfm]

On 29/06/2021 at 7:19 PM, kasper said:

Agree on the epoxies.  I’ve built using t88, west system and boat cote. 
 

I’ve always done post cure heat treating and the only one that’s a not to use again is boat cote.  The issue is the low thermal softening point even after post cure treatment.

 

I used it to build a white fabric wing and the measured temp inside the wing was too close to the thermal point of the glue for my liking. 

I'm confused.  The heat distortion temperature of West system is 50 deg C..  Bote Cote is 55 deg C???

[kasper]

6 hours ago, duncan_rtfm said:

I'm confused.  The heat distortion temperature of West system is 50 deg C..  Bote Cote is 55 deg C???

I can only say what I've experienced. T88 out performs bote cote when I have used it.  

[onetrack]

Isn't there a good Sikaflex structural adhesive available as an option? - such as Sikaflex 292i? That product will cope with 90°C.

[Blueadventures]

8 hours ago, duncan_rtfm said:

I'm confused.  The heat distortion temperature of West system is 50 deg C..  Bote Cote is 55 deg C???

Duncan  if your close to Caboolture drive to the airfield and at the Gliding club ask for Bert, I saw two vintage aircraft he built with original metal parts and all new timber and covering, he is a legend and knows about this stuff and the glues and the preparation to glue.  If you find him and he has time take notes or even record on your phone what he tells you.. I have learnt great stuff off him and Bernard (Speedy) in the past.  Worth the travel I reckon.

[duncan_rtfm]

Sikaflex structural adhesive?  I'll Google it.  Thanks.

 

Actually, Caboolture isn't that far from me.  Thanks for the heads-up.

[facthunter]

Something I've been thinking of for a  while. Your  rear wheels look too far aft of the CofG This could make landing  difficult  so ask about. Better to do it now than later. Nev. 

[kasper]

34 minutes ago, facthunter said:

Something I've been thinking of for a  while. Your  rear wheels look too far aft of the CofG This could make landing  difficult  so ask about. Better to do it now than later. Nev. 

Not sure I agree on this one ... the CofG of the aircraft is not on the CP of the front wing ... it is between the CP of the front and rear wings based on their shared load of the lift provided at touchdown/takeoff.  as a rule of thumb most fleas are considered safe if their CofG is at around the 25% of combined chord of the two wings plus any gaps. 

 

That would put the CofG only just in front of the main wheel of this design.

 

To correctly work out the furthest rear point for the CofG you need to calc the lift splits front/rear accounting for all interwing impacts on the lift achievable from the rear wing from the front wing

Fortunately is generally is the case that the front wing lift becomes critical first and you work off the max lift the front wing will produce at max AofA and that sets the lift split between front/rear and you have a safe point.

 

Never forget - the flea/tandem wing is really a canard and front wing dictates the minimum speed and the lift split and CP posiutions of the two lifting wings sets the effective angle of attack for the fuselage and from that you can work the overall CofG and the approx landing/takeoff angles that will then dictate which wheels touchdown/takeoff first.

 

eg for the HN290 and 293 tailwheel as designed they naturally three point in the landing config because on full back stick in the hold off the fueslage adjusts with reduced rear wing lift to touch the tailwheel just before the mains - equally on takeoff the mains lift before the tailwheel as the front wing lifts them off before the rear wing can lift the tailwheel.  NEVER try to 'wheel' land or 'wheel' takeoff a tailwheel flea - you will find you need to be over 70knts to get the damn tail up and you do not want to be anywhere near the ground at that speed with a short coupled undercarriage.

 

Lots of fun with pous but I would strongly disagree that the main wheel positions for this one are at all too far aft.

Edited July 9, 2021 by kasper

[facthunter]

At times there's going to be a lot of weight on the nosewheel and the fuel could not be in a worse place for change of CofG. The Saddler Vampire once the rearwheels contacted just fell on to the nosewheel whatever you did, causing a few failures and making it unpleasant to land.  We know where the static CoG is  The centre of lift is the question.. What great problem can happen if there's less weight on the nosewheel? Nev

[duncan_rtfm]

Hi,

I have also been uncomfortable with the gas tank position.  It needs to be closer to the CG, but that is easier said than done.  But you raise a very good point.

[kasper]

All else fails consider a tank in the centre section front wing behind the spar.  Yes the weight for the fuel is behind the pivot so when standing still you have to lift the weight on the control stick in addition to the wing weight but as soon as the wing lift starts it disappears. 
 

you could have 10-15l up in the wing and a 5l tank further back from the current position to get your cofg movemenet reduced full to empty fuel