August Issue Feedback

[airman]

Alex Whittaker in Weekends, was taking about how cheap metalworking lathes are becoming.
Would it be possible for Alex to do series on using lathes. Starting with the basics, like sharping cutting tools,etc.

[Mike Rolls]

Editorial – I’m glad I’m not the only one who finds the standard of U/C attachments poor in so many of the ARTF designs. The only good one I have found or even seen so far (admittedly, not from a very large sample) is the RCM Dingo from Puffin Models (an excellent model in all other respects as well). Looking at some designs I do wonder if the prototypes were ever landed on a typical club grass field.

Switch on/Trade Account/Counterpoint – as ever, a useful set of snippets.

NPM Fury Interesting review, especially about the U/C. One point – what servos were used? The data panel says HS65s, the test says HS56s (twice).

Chrislea Super Ace – super article!

Power for peanuts – good information and well worth reading.

A Good Vintage – again – well worth the read

Thunder Tiger F-75S – virtually five pages on a review of a single engine is a bit over the top to my mind – it could easily have been condensed into 3 without losing anything.

All Write – I always like to hear the views of others.

For Starters – well written for the intended audience

CAP 21 – lovely looking little model – shame about the ugly lump of metal sticking out the top! Surprised that Peter hasn’t used a symmetrical section on such a model – at 20 ozs/sq.ft it shouldn’t be running into low speed handling problems.

F5E Tiger II – my first ARTF was a VMAR product, which put me off the brand for life. The tale of bits falling off didn’t come as a surprise!

Honest John – very enjoyable article

Balance of Power – something that has been badly needed – a review of the nightmare of compatibility/non-compatibility of balancers. Would have been even more useful with a table showing as many Li-po manufactures as possible against the type of connector – for example Kokam packs are popular and I know that their connector is not the Enerland type but I’m not sure which they are.

P-51 – a very good review drawing attention to the good and bad points of a model which, at first sight, is very attractive but which as a package has some severe problems.

Project Bushwacker – to be honest this seems never-ending. On the other hand, the level of detail is good for a beginner, covering a lot of points.

Bury’d Treasure – lovely photos, good text. One point – Colin Auton’s ‘short nose 190-D’ – Eh? The Dora is the long nose version of Kurt Tank’s masterpiece – the photo is quite definitely a short nose and is captioned as an A4 which would be right – so we’ll forgive Alex for a slip of the pen.

Piper Cub – fair seeming review of a nice looking model and less verbose than some reviews of late. However – like Peter Miller I am puzzled at the reference to ‘short coupled models being prone to tip-stalling’. It’s something I have never heard claimed before and would welcome an explanation.

Katana S 30E – nice looking model and I liked the printing of the views of two pilots of differing ability.

Parting Shot – love it!

All in all – a good issue. Now if only it included some none R/C stuff……

Mike

[Tim Mackey]

Nasasteve....this is not the only forum you and I regularly contribute to :)
I may of course have an AKA elsewhere :):)

[nasa_steve]

timbo
i thought as much now you got me thinking pm me on the otherside to comfirm my suspitions
regards
nasa

[Slopetrashuk]

Do you two need to get a room?
;-)

[Braddock, VC]

I liked quite a bit of this month's mag, especially the candour that seems to be creeping into the reviews.
With regard to the cub, short coupled and tip stalling, I think that this should have said perhaps they're more prone to t/s, as in my experience with the yt one it was possible to change attitude/direction v.v. quickly and mine bit the dust as a result, it's probably due to my limited ability as a pilot but it was repaired and lived to crash again; on this occasion I like to think it was rx problems rather than my stupid digits.
I'm not fussed about electric or scale preferring model aircraft to resemble, well, model aircraft and that's why I enjoyed the bush wacker article, after all we can all learn or relearn something valuable from such scribings.
I did get enthused by the cap plan but why the ffffflipping heck PM stuck the engine out like a chancre is beyond me. Dimensionally I think that new saito 40a will fit in no problem but only if I can't get my mate to part with an OS wankel.
Trade account was interesting as was andy ellisons a cert thingy as for the rest it didn't move me much apart from, of course, the readers free ads which has to be the most avidly read bit of all for me.
If you asked me what I'd most like to see included it'd be how to repair artf fus' and a bit of thermal without the electrickery, I'd also like to see an article or two on pylon racing, but only if it's ic.
BTW, it's also impossible to get too many cubs, I have two to finish and I'm looking for a third.....

[Mike Rolls]

John
One of the reasons for short coupled a/c was the perceived ability to change direction quickly (I say 'perceived' because as in the words of the song 'it ain't necessarily so') but that doesn't have anything to do with tip stalling as such - or if it does, I've never found any mention of the fact in anyhting I've ever read on aerodynamics.

Mike

[Peter Miller]

Why do I use a flat bottomed section? Because in the way that I use it it works just like a symmetrical section and is much, much easier to build. If you read the sequence it is built flat on the board until all the sheeting is completed and the capstrips, I never, ever get a warp in one of these wings.
The wing is then set at 0 degrees incident measured on the chord line, not the bottom of the wing as so many people do it.
As for exposed engine. Even the .32 would be exposed when it is side mounted and then the silencer would have no where to go.
I doubt that a Wankle engine would go in the cowling.
Wait until you see my next one. 1/6th scale piano hinges essential and opening aluminium side panels. Lots of stringers and a flat bottomed section because it is scale.
Still no explanation on that tip stalling question, I wonder why?

[nasa_steve]

why not build the cap with a nice smooth running electric up the front then you could build a nice cowl around it. motor wise i would be looking around an AXI 2820/10 or AXI 2826/12 that would be pretty awsome for power.
nasa

[Tim Mackey]

No I dont think Steve and I will bother with the room thank you Andy - LOL

Steve....so you are supicious of too !! This is becoming a habit, first JETSOME AKA JOHN, now the NASA boy !!

I have PMd you over "on the other side" :-)

I think this thread has drifted a little off topic dont you ... LOL

[nasa_steve]

just eh bit eh;-)
steve

[Mike Rolls]

Peter
Yes, I've designed and built models with sections like that and for the same reason. Certainly for much sports R/C work they are perfectly adequate but it is not accurate to say that they work the same as a symetrical section - you'll never find a C/L stunter (whether model or modeller) making that claim.

Mike

[the unmagnificent man]

Nasa SteveThank you very much for taking the time to help me out. I have seen the website and all has been revealed. I now have a far better understanding of whats going on.
TimboThanks also to you, I still check out the watts up thread when I need to work electrickery problems out. Al

[Rob Barrett]

Just to say thanks to Andy for the BRILLIANT "For Starters" series, in RCM&E, during 2007. I'm new to RC and this series has been a great help to me. Just one thing - can you sort us some decent weather or the "A Certificate" will have to go back to 2008 ! Rob.

[Peter Miller]

Steve, if you want to put an electric motor in it feel free...just don't tell me about it.

Mike
No, but I use NACA 0018 in a control line stunter, not a 12% section and control line stunters are flown to much greater precision than any R/C model.
I originally got the idea from a full size fighter. Let's see if anyone knows which aircraft that is.

[Slopetrashuk]

...Just to say thanks to Andy for the BRILLIANT "For Starters" series, in RCM&E, during 2007. I'm new to RC and this series has been a great help to me......
Rob.


Just one more part to go Rob. Including dealing with some of the sneaky tricks Examiners get up to during the test.......

Glad you liked it.

Andy

[airman]

It was reported by Alex Whittaker,in his East Anglia Show report, that the BMFA has banned the use of smoke in displays at model aircraft shows.Why?
I was at the Flying Legends airshow at Duxford yesterday.Some of the fullsize aircraft were using smoke during their displays.One of the displays with four Steerman aircraft, produced so much smoke that you not see across that airfield. The commentator , announed that the aircraft were using bio-degradable fuel to produce the smoke!!
Also yesterday popstars were telling us to save the plant, at concerts across the world.This according to the newspapers, this event produced 74500 tonnes of carbon emissions. And also produced 1025 tonnes of waste at the stadiums.
But the BMFA will not let model aircraft pilots use a few litres of fuel for displays.
This should have been posted on the BMFA forum, but this has been closed down.

[Braddock, VC]

Mike and PM,
The reason I suggested that was my YT cub, same size as the WM one, changed direction that flipping quickly that the speed scrubbed off and she just fell out of the sky.
I had to do it, someone decided to run across the strip just as it got to head height after take off, really peed me off.

[Peter Miller]

John,
You accident was due to trying to turn too low and too slow. I do sympathise, I lost one of my best control line scale models at Old Warden many years ago in the same way, uncontrolled brats running across the circle as I was taking off.
Our point is that Maurice Ashby stated that a short coupled model i.e. one with a short moment arm was prone to tip stalling.
There is absolutely no reason why a short moment arm would make a model prone to tip stalling that we know of. And anyway, the Piper Cub has a long moment arm, exactly 1.5 chords which is longer than many aircraft.
If you look at the picture at the heading of this posting you will see my Culver Dart, not only has it an ultra short moment arm, it has sharply tapered tips going to almost a point.
The tip shape could easily generate a tip stall but it doesn't on the model which is most forgiving.

[Mike Rolls]

Dave
My reading of Alex's article was that the 'oil ban' was a leg pull. Yes? No?

Mike

[Former Member]

[This posting has been removed]

[Former Member]

[This posting has been removed]

[Slopetrashuk]

Me- Either a typo or too many Stan Yeo models in the Skunkworks.....
;-)

Andy
Who sometimes types faster than he thinx....

[David Ashby - Moderator]

Yes Mike ;-)

David

[Peter Miller]

Ref: Eric's comment. To expand, the longer the moment arm, the smaller that tailplane can be. The Cub has a long moment arm. If the tailplane is small and the moment arm is short then the CG has to move forward. The cub has a pretty reasonable size of tailplane, I estimate about 15% of the wing area.
If the CG is too far back a model will be very sensitive to the elevators and a sudden pitch up could cause a tip stall, this is related to CG location, not moment arm.
Unless, of course, Maurice Ashby knows better.