Re: CEF speed contest Design Discussions

roddie Fri Apr 18, 2014 9:26 am

OVERLORD wrote:I tried to get mine in the air the day before yesterday in my neighbour's garden. It was quite a failure. Scale landing gear and 1/2A don't go together well. As soon as the tail lifted, the prop touched the ground. There can be 2 reasons for that:

1. The landing gear is too low. Before, I held the plane in a for me horizontal position and it seemed to be OK. Probably, my impression of "horizontal position" does not match reality.
2. As with Ron's plane, the nose goes down. Then the landing gear is too far back.

As an emergency, I replaced the wheels and fixed 60mm diamater doped cardboard wheels to get a bigger ground clearance. I also fixed a M6 nut on the tail. I hope the CG is still OK. On the grass, I laid out wooden planks for approx. 3m. I think this might not be enough in length. How far a distance such a model usually rolls before taking off?

I'll try again today.

Lieven

Lieven, your "finish" photo shows a black prop... your "construction" photos show a grey 6" x 4"... Is the black one also a 6" x 4"??? If so; try to find a 5" x 4".... 5" x 3.5" or a 5" x 3" which will give you a full inch more of clearance. This may not solve your trouble with nose-overs... but if your prop is 6" diameter.. and hitting the ground while level... it will help that.

You shouldn't need more than 3 meters of taxiway.. but it depends on how heavy your model is. I used to use large cardboard panels taped together.. laid out on the ground.. or also tarpaper. Are you giving full "up" elevator on release? That's generally a no-no... but; the prop-blast over a full-up elevator will help keep the tail down when taxiing... but also can keep the model from gaining enough speed for take-off. It would be a balancing-act... but something to try.

A word of caution... the new cardboard wheels you made, are probably a lot lighter than the original ones... and adding the M6 steel nut as tail-weight has relocated your CG a LOT... maybe it's "spot-on" now... but if you feel it "could" be tail-heavy... don't fly it that way. Remember; "nose-heavy" will fly... "tail-heavy" will fly... uncontrollably... usually resulting in a broken airplane.

I hope these suggestions help. Good luck!!!!!

OVERLORD Fri Apr 18, 2014 10:11 am

Thanks for your tips guys. I use a 5.5x4 prop cut down to 4.75. Without the nut, the plane balances on the leading edge at the wing tips.

Lieven

getback Fri Apr 18, 2014 6:35 pm

Ron sorry to hear that your having issuses I Know u can get it straightened out though , My self a lot been happening and [bleep] poor weather is going to set me back if Jim will allow me ....... plans were to fly this afternoon cooling fast wind good about 5, on the way home I was thinking this is going to bee it and then on the drive home my friend from work was on the side of the road broke down ..Stoped gave him a tow with the strap he had to a friends, the fuel pump is the corpret after checking a few other things . anyway drizzle cold almost dark ...But NO wind so St.Pats Beers

the ready for spring weather Eric Laughing

JPvelo Fri Apr 18, 2014 7:01 pm

Fitting that the contest organizer had the first major casualty:
CEF speed contest Design Discussions - Page 36 KrY9RtZ

This is exactly what happened to the real Miss Ashley. Do I win the scale part of the competition now?
lol!

**Cribbs74** Fri Apr 18, 2014 7:08 pm

Crap!

What happened Jim? Besides the obvious that is...

It can be repaired, just won't be as pretty.

Ron

Edit: I went ahead and gave you a greenie for the great picture.

dckrsn Fri Apr 18, 2014 7:12 pm

Ugh, Jim.That blows big time.
On the other hand, I still see a plane.
You just nocked a little pretty off her.
There's plenty left.
Cary on sir.
Bob

getback Fri Apr 18, 2014 7:16 pm

Man that assfalt is hard on a plane going fast!!! Sorry to see that

our forecast looks like Monday?!

http://www.weather.com/weather/5-day/27283 Biplane

**RknRusty** Fri Apr 18, 2014 8:01 pm

Ouch, Jim! That was one of my favorites. I bet it looks worse than it is though. They usually do.

The April showers started too early today. Rain and 15mph tomorrow. I apologize to the Contest Director for pushing the time, as I know that is aggravating. But now I've got a really cool little plane to play with.

Now I feel bad for grumbling about the Choir scrubbing my attempt in their church yard. I'd totally forgotten that Easter preparations would be in full play this week.
Rusty

pkrankow Fri Apr 18, 2014 8:08 pm

Hit it with some CA and try again!

I hope to get to fly, but it is looking bleak...Mom is back to work.

Phil, AKA Mr. Mom

roddie Fri Apr 18, 2014 9:08 pm

pkrankow wrote:Hit it with some CA and try again!

Sorry Jim... that's disappointing, but I agree with Phil!!! CA works awesome on small profile models.. repairs are strong and add virtually no weight. I used to take tweezers and pull off any bent splinters until the parts would fit all the way back together. Hit it with some thin CA.. wipe a little spackle over the crack.. sand and touch-up. Miss Ashley will be back in business in no time flat!!!

duke.johnson Fri Apr 18, 2014 10:56 pm

Jim
I talked to others about this before, "they always fly better after you have glued the tail feathers back on!".

ian1954 Sat Apr 19, 2014 5:18 am

I keep tuning in to the competition with baited breath. I am 5+ hours adrift in the UK (all depends which part of the USA you are in) and read about the preparations, the attempts, the issues .......

It is like being addicted to a "soap" story on TV. The fuel tank, the landing gear, the propeller ........

I awoke this morning to see a casualty .......... very sad.

But like any drama series - all we see is the picture of the damage and we are left in suspense.

Did it fly 10 laps at 0.1 second per lap before the photo was taken? Will it return from the "hospital" rejuvenated? Are the fellow contestants really sympathising? (I had to put this in - it is a contest!)

Keep calm and carry on watching!

JPvelo Sat Apr 19, 2014 6:57 am

Ian,
Because you are so closely following this and in honor of the Easter holiday, I will do my best to have Miss Ashley repaired in three days.

Also, due to the fact I have only received one video stay tuned for the NEW deadline.

Jim

roddie Sat Apr 19, 2014 6:59 am

ian1954 wrote:I keep tuning in to the competition with baited breath. I am 5+ hours adrift in the UK (all depends which part of the USA you are in) and read about the preparations, the attempts, the issues .......

It is like being addicted to a "soap" story on TV. The fuel tank, the landing gear, the propeller ........

I awoke this morning to see a casualty .......... very sad.

But like any drama series - all we see is the picture of the damage and we are left in suspense.

Did it fly 10 laps at 0.1 second per lap before the photo was taken? Will it return from the "hospital" rejuvenated? Are the fellow contestants really sympathising? (I had to put this in - it is a contest!)

Keep calm and carry on watching!

Sure; I'm wondering what exactly happened to Jim's airplane.. does it matter? There were no personal injuries reported.. which "is" the important thing.

I looked at his photo and saw his model as my own.. We (contestants) have helped each other along the way through every aspect of this contest.. and I'm quite certain that those who've commented "sympathetically" have done so in sincerity.

**RknRusty** Sat Apr 19, 2014 8:27 am

JPvelo wrote:Ian,
Because you are so closely following this and in honor of the Easter holiday, I will do my best to have Miss Ashley repaired in three days.

Also, due to the fact I have only received one video stay tuned for the NEW deadline.

Jim

That's wonderful, Jim. I'm glad to know I'm not the only dragass around here. Now I know if I ever CD a contest to build in a super secret second deadline. An SSSD. Looks like good weather is coming in my region fairly soon.
From what I've read here and there, I'm guessing our buddy Navion is the punctual member of the group.
Relieved Rusty

OVERLORD Sat Apr 19, 2014 10:46 am

I'm glueing as well. Yesterday afternoon, after your precious avice, with a large piece of cardboard under my arm, I went out to give it a go again. The bigger wheels were not of much use. The plane definitely goes nose down. Tried to hand launch it but it didn't seem to have enough speed. After closing the needle 1 more quarter turn I got some more revs out of the engine. I launched it again and then it kind of flew for 10m before hitting the ground: the engine mount broke off the fuse and also had some cowl damage. Luckily, I did found all the bits for the reconstruction.

When looking at Jim's video, his plane shoots forward like a rocket. Mine rather starts rolling like a tractor. I've got the impression that the prop turns in a vacuum as sometimes happens with speedboat props.

Yesterday, I was really p... off. I was seriously thinking of changing hobbies. Why not darts, or playing cards, or staring whole day at a vintage stationary engine, one of those hit and miss ones!!

Lieven

**RknRusty** Sat Apr 19, 2014 12:10 pm

OVERLORD wrote:...Yesterday, I was really p... off. I was seriously thinking of changing hobbies. Why not darts, or playing cards, or staring whole day at a vintage stationary engine, one of those hit and miss ones!!

Lieven

Lieven, if it was easy, everybody would be doing it.
Rusty

roddie Sat Apr 19, 2014 1:04 pm

RknRusty wrote:
OVERLORD wrote:...Yesterday, I was really p... off. I was seriously thinking of changing hobbies. Why not darts, or playing cards, or staring whole day at a vintage stationary engine, one of those hit and miss ones!!

Lieven
Lieven, if it was easy, everybody would be doing it.
Rusty

It's a wonder I've stayed in this hobby (all of you CEF members have helped GREATLY) because I've never flown with a group.. always alone. I've had enough good experiences to overcome the not so good ones I guess. I often think about what it would be like if we all lived in the same area. It would surely be a catalyst for me to fly more.. and get some of those kits built.. but I'm working on it now; more than I have in the last 20 years.. since joining this forum. I have all of you to thank for that!

batjac Sat Apr 19, 2014 3:14 pm

JPvelo wrote:Ian,
Because you are so closely following this and in honor of the Easter holiday, I will do my best to have Miss Ashley repaired in three days.

Also, due to the fact I have only received one video stay tuned for the NEW deadline.

Jim

Only one video? I WIN! I WIN! I WIN! lol!

Just kidding. Looking forward to seeing how everyone else fares on their flights.

And believe me, the only way I could win is if I WERE the only video that was submitted. My video is actually the video of the maiden flight. I only got three flights in before the grass landings took their toll, but all three flights averaged the same lap time, so the maiden it was.

Now it's time to lighten up the plane and mount the PeeWee on it.

C'mon guys, let's see them flights.

The Finally Done Mark

navion34 Sat Apr 19, 2014 3:46 pm

batjac wrote:
JPvelo wrote:Ian,
Because you are so closely following this and in honor of the Easter holiday, I will do my best to have Miss Ashley repaired in three days.

Also, due to the fact I have only received one video stay tuned for the NEW deadline.

Jim

Only one video? I WIN! I WIN! I WIN! Just kidding. Looking forward to seeing how everyone else fares on their flights.

And believe me, the only way I could win is if I WERE the only video that was submitted. My video is actually the video of the maiden flight. I only got three flights in before the grass landings took their toll, but all three flights averaged the same lap time, so the maiden it was.

Now it's time to lighten up the plane and mount the PeeWee on it.

C'mon guys, let's see them flights.

The Finally Done Mark

Hi I post my video, maiden flight like you mate... So I presume that 2 videos are sent...

JPvelo Sat Apr 19, 2014 9:46 pm

Allright,
Since I have received a total of one video we will extend to midnight Friday May 16. This should give everyone plenty if time to sort out issues and let weather clear up. It will also allow the CDs work to calm down and for him to return from vacation.
If there is enough final participation to warrant having the contest next year it will be pushed back to May for the same reasons.

Jim

JPvelo Sat Apr 19, 2014 9:50 pm

Lieven,
This hobby can be extremely frustrating. My Miss Ashley was flying perfectly two months ago. I can't get a proper run out of her now. The other day the motor was surging so bad she bounced, and surged to full scream on the bounce. You see the results.
Just out of curiosity, are you using a stock single port motor?

Jim

**RknRusty** Sat Apr 19, 2014 10:22 pm

JPvelo wrote:Lieven,
...The other day the motor was surging so bad she bounced, and surged to full scream on the bounce...

Sounds like your reed might be floating.

JPvelo wrote:Allright,
Since I have received a total of one video we will extend to midnight Friday May 16. This should give everyone plenty if time to sort out issues and let weather clear up....
Jim

Jim, that's wonderful, thanks. May is the month of dependable outdoor planning just about everywhere. We'll be able to test and tune and get some quality flights in. March and April are tough months. I might even get another Cox engine flight time logged for Ron's contest. Time is running out for that too.
Relieved Rusty

OVERLORD Sun Apr 20, 2014 5:22 am

JPvelo wrote:Lieven,
This hobby can be extremely frustrating. My Miss Ashley was flying perfectly two months ago. I can't get a proper run out of her now. The other day the motor was surging so bad she bounced, and surged to full scream on the bounce. You see the results.
Just out of curiosity, are you using a stock single port motor?

Jim

Jim, No, the cylinder has 2 ports and I use a TD head.

JPvelo Sun Apr 20, 2014 7:28 am

OVERLORD wrote:
JPvelo wrote:Lieven,
This hobby can be extremely frustrating. My Miss Ashley was flying perfectly two months ago. I can't get a proper run out of her now. The other day the motor was surging so bad she bounced, and surged to full scream on the bounce. You see the results.
Just out of curiosity, are you using a stock single port motor?

Jim

Jim, No, the cylinder has 2 ports and I use a TD head.

Hmmm,
Seems like it should have more pull than what you're describing.
Once you get to where you can take off (and you will) without damaging the prop order some apc 4.75x4 props. They are consistently my fastest prop but they break if you even look at them wrong.

Jim

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