Mark's Rutland A4 Skyhawk

[Steve McLaren]

Up early? or is that up late? Either way, I admire your your commitment Mark. Hope you make it in time!

[Mark Kettle 1]

No up early, had a pick up in Nottingham at 04:00 for Stansted so I did about 1 hour worth.

[Mark Kettle 1]

Now running out of grey film and time.

[Mark Kettle 1]

Well I've patched it.

[Mark Kettle 1]

Well I've bolted it together other than the cockpit.

Radio works just need to tame control deflections, and put he decals on. Weighed it with battery, cockpit stuff and shrouds and hook - 36 oz and balanced with no lead ballast needed, I did bring some of the gear forward a little to help with that. 

Edited By Mark Kettle 1 on 09/09/2016 12:56:49

Edited By Mark Kettle 1 on 09/09/2016 13:02:13

[John H. Rood]

Lookin' GOOD .... go man, go! You got this!

[Harry Twist]

Rapid progress Mark and she is shaping up to look great !

[Mark Kettle 1]

Cheers lads, we arrived in the area - we are at Rhuddlan 19:00 just had an evening meal, I'll do a little more to my Skyhawk.

[Tim Mackey]

GO Mark !!!

[Chris Barlow]

You'll be finishing it slopeside tomorrow then Mark?

Will the glue be dry before the maiden?

Very impressive speed build.

[Mark Kettle 1]

Well did a bit more in the room, painted the pilot, hook, put the stickers on going bed now.

[Peter Garsden]

Excellent Mark. This group should be renamed the Power Scale Soaring Insomniacs Association.

Shower S*** and Shave and off to the Orme - see you all later

[Peter Garsden]

No No PISS - "Power Insomniacs Scale Soaring" Ha!

[Chris Barlow]

Posted by Peter Garsden on 10/09/2016 06:29:41:

No No PISS - "Power Insomniacs Scale Soaring" Ha!

You're definitely getting moderated for that Peter!

[Mark Kettle 1]

LOL see you in a bit you lot.

[Mark Kettle 1]

Yesterday we assembled up the Orme, the wind didn't play ball to test fly our new creations. Today Sunday 11th September is the official meeting day for Mass build event and there's a good chance the wind will be with us today. On Saturday we lined up the models much like jets at a international air display the few that were there looked fantastic.

[Mark Kettle 1]

I thought I would do a review entry on my A4 flight after our great Mass Build PSSA event, followed with me showing the few repairs needed, the reason I had a little bump when I first flew it.

Luckily I think I got away quite lightly on the repair side, when you think how many rocky out-crops at the Orme. I've taken off the stickers after warming them between my hands and placed them on a plate, and I've set too gluing in a bit of balsa in the dent and running glue into some of the cracks around the fuselage joints near the nose.

Surprisingly the pilot didn't break off.

From my launch made by John Hay, it flew out lovely, climbing away lovely and didn't need any trim or corrections, however that was until I put in the first control inputs in and I had far to much control deflection, I can't add much more on the flight because I flew only for a little time.

Prior to flying I was asking others that had flown and who had enjoyed longer flights than me ( I'm laughing whilst I type this ) about their actual control deflections used.

The 15, 12 or 10 mm +/- mentioned in magazine article being across either the ailerons or elevator got me thinking prior to flying and whilst on the flight line that these are a little to much. I had turned them down a little after showing one or two flyers, but at launch I still had far to much roll etc.

To help with setting up the ailerons and elevators I've made a tool for setting the controls :

[Mark Kettle 1]

Here it is attached to the wing edge :

I've already marked it off the paper covered side with some 6 and 8 mm graduations which are approximately half of what I had on the day.

I'd would welcome input from other builders and flyers on their experience on the control deflections used.

Right I'm getting the covering iron fired up !

[Steve Houghton]

Hi Mark,

I'm following this with interest. Having failed to make my A4 flyable for the event, I am now setting up the radio and throws. I am currently using Phil's recommendation of:

Ailerons +15mm-10mm

Elevator +-12mm.

Like you, I'd be interested in feedback from those who achieved successful flights about their actual control throws.

[Steve Houghton]

P.S. I like your 'throw-ometer'!

[Mark Kettle 1]

I like that a Steve .

'Throw-O-Meter' - it is.

Edited By Mark Kettle 1 on 28/09/2016 12:45:12

[Mark Kettle 1]

I forgot to mention the fin broke off and that's been glued on with pva.

[Phil Cooke]

Hiya Mark, good to see your Skyhawk repairs well underway in ample time ahead of our next meeting 8th/9th October!!

As for throws, this is what we stated in the 'Build Guide' thread (you may remember the figures originally printed in RCMW magazine were incorrect and grossly over specified!)

"The A-4 is a responsive model as you might expect, and the throws needed are only small, I would set up something like;

Elevator +/- 12mm

Aileron +15mm -10mm

with a healthy dollop of expo to keep things smooth around the centres."

They were my estimates earlier this year having flown the prototype on numerous occasions over a single weekend in October 2015. That model was then sold back to Traplet for commercial use and I didn't fly it again...having had some more stick time now on the type I'd say the quoted elevator movement is about right, but the ailerons at +15mm is too much...

I've just re-measured my movements on the 'production' build A-4 after a little refinement post landing on my first flight. It's worth saying I flew with Rates ON throughout the Mass Build weekend - I never felt the need for more throws, even with a slightly nose heavy model on the maiden. I did reduce the expo on elevator a little from what was initially set. So this is what I have set up now...

Rates ON

Elevator +/- 10mm with -30% exponential

Ailerons +8mm -5mm with -30% exponential

Rates OFF

Elevator +/- 13mm with -35% exponential

Ailerons +12mm -9mm with -40% exponential

Since the maiden flight I've also programmed in some down elevator compensation for when the draggerons are used on landing - each aileron goes UP by 8mm and this caused a pitch up reaction - easy enough to combat with about 1/3rd down elevator stick - this equates to 3mm down elevator now mixed in when the brakes are deployed.

Desperate to fly mine again, will be good to see them all out on the Orme in a couple more weeks...

[Mark Kettle 1]

Thanks Phil for the flying experiences and control throw details with your A4. I'll make a new paper front to my 'Throw-O-Meter' with those settings and make adjustments.

It with soon be back together as it was on the morning of the event.

Edited By Mark Kettle 1 on 28/09/2016 20:42:46

[Peter Garsden]

I agree with Phil though so much expo I find produces mush at centre then nothing followed by sudden rush of over control. I would go for less expo on elevator and more movement. Ailerons I agree same expo but less movement. I was using the lower rates quoted by Phil all weekend in the high winds. Didn't need full rate. The ailerons are lightning response but the elevator less so.

Edited By Peter Garsden on 30/09/2016 18:00:45