Patterndude1

Guys, I think the Integral is an awesome airplane and it fly's very well, but there was an incident here with one the other day that didn't please me to well. Some of you might know Mike Pascal " D6 Member " who fly's pattern now in Intermediate. He ordered an Integral seven weeks ago and just finished it two weeks ago; he went out and flew it last week and he had to put the battery pack 16.5 inches behind the center of the wingtube not to mention the 6.5 oz of weight he already had in the tail but the plane never ceased to be nose heavy. He has a YS. 160 DZ, with a short tuned pipe in the nose.

A day before he flew it I noticed that where the Carbon Fiber stops aft from the firewall (3 in. aft), it did not have that much strengh between the area where the Carbon stopped and the wingtube. He had a dead stick on his maiden flight last week, came in on final and right when he was 5 in. from the ground he stalled it and it hit the landing gear ( Not to hard as each airplane is built to resist the breaking point and it didn't even scrape the chin cowl, the wingtips and plus didn't even skin the wheels it hit so lightly). Right between the Carbon Fiber endpoint and the Wingtube it broke in half at that middle point where the fusealage seemed thin. It ruined the airplane, and he was very dissapointed in the building and the issues he had with the nose weight and the weak point in the aircraft.

I was writing this to see if anyone else have had these problems with another Integral or not because I know it isn't a bad airplane. I think it fly's superb, but this could be the result of a incident at the factory??? Not sure??

I have four pictures of where it broke which I will post later.

Thanks,



Matthew L.

kcnelson

On my Integral the CF ends about 2 inches behind the gear, and probably 4 inches ahead of the wing tube. I have had some "heavy" landings without any problems. In September my right wing tip got hit on the ground by another airplane. The wing was destroyed, and the torque on the fuse caused some wringles behind the canopy but no problems ahead of the wing tube. I have a rather large opening on the bottom for cooling (I'm running electric) ahead of the wing tube, so the bottom would have less strength than with a glow engine. I would want extra strength to extend from the firewall at least to behind the gear. I suspect the lever action of the DZ against the gear was just too much for a non-reinforced nose. It does sound like there might have been a production problem, or worse yet a design change.

Ken

Patterndude1

I'm electric myself, but that is exactly what I feared.

Matt

KFM

Hi Guys
I bought an Integral last year not yet flown nearly ready to fly I to am having problems with the CG I have fitted a Ys 170 + short pipe rudder position as shown in the instuctions have put a few carbon tows in the under carrage postion as I have seen some that have cracked the fuz in that area the CF on mine is continuous from the under carrage past the fire wall to the nose ring the battery is fitted at the back of the tank support the CG in the instuctions does not seem to be correct other pilots say the CG is about 167mm from the front leading edge of the wing I will need to add weight at the tail not sure how much yet if a lot is required may consider having the rudder servo moved to the back end other Integrals fly well may be the construction in build is not quite correct
KFM

handglider

My Feedback: (23)

Hi Matt,

Sorry to hear of Mike's problems, just hate to hear a story like that.

Hey - I am hoping to make it to dixie this year! Looking forward to seeing my D6 friends soon.

best of luck, dean

patternflyer1

My Feedback: (11)

Hey Matt.

Good chatting with ya the other day!
Lets see some pics.. Seems odd. I have seen some of these survive with fairly rough landings.

Chris

cchariandy

No problems with cracking on mine after 120 flights. Mostly soft landings with one exception that resulted in some very minor bulging at the fuse sides in the area of the landing gear plate.

They are nose heavy with the YS170/Short pipe combination so you have to use a light spinner, wheels, wheel pants and place your rx pack down the turtle deck as far as you can reach. If that is done you should be able to achieve 167 with no tail weight. Mine is at 175 with 1/2 oz in the tail.

The weight of the landing gear is quite variable so if you got a very heavy pair you may not be able to achieve your cg target. Weigh them and replace them if they are too heavy. That would be far better than adding a bunch of lead to the tail.

Colin.

Nickolas

Hi faced similar issue two days before the European Championship in 2008 please see this thread:

[link]http://www.gbrcaa.org/smf/index.php?topic=1335.0[/link]http://www.gbrcaa.org/smf/index.php?topic=1335.0

I made some comments about the strength of the plane in CARF Integral Kinda Build Thread but I received no answers from the reps. I am 100% that my case was a structural failure.

If you have some spare time please see the video of the repaired Integral this is the way I used to land the plane, only once I had a dead stick and the landing was a bit more heavier and that cost me a fuselage.

Anyway now is fixed and of course I fly the plane as a B model.

Regards,
Nikos

Nickolas

More pics from the repaired Integral here:

[link]http://www.aeromodelling.gr/ForumS/index.php?topic=6306.0[/link]

It still flies pretty well, with some pitch and roll coupling and of course very nose heavy...but I can stand it...

Patterndude1

Hello Dean, it is nice talk one of my buddies again. I hope to see you at dixie.



Matt

Jeff Boyd 2

WOW . . better have a look at mine [:-]

I have quite a few flights on mine now with no issues . . even A deadstick down wind on a VERY windy day. Just made it back over the crop and DID land it kind of heavy . . BUT no issues . .

Anyway, I'll have a closer look at it now

Cheers, JB

handglider

My Feedback: (23)

Hey Matt...

Kathy and I are planning on attending one of the Crowley meets - maybe both. It's not any further for me than those florida meets and way better food.

I just sent you a PM.....

LCHelilover

My Feedback: (15)

Hey Dean,

Plan to come over to Lake Charles (Sulphur- LARKS), too, while you are at it. It's only 40 more miles from Crowley! We have cajun food, too!

G

handglider

My Feedback: (23)

Hey George,

Do you guys have the D6 schedule up yet? I just need to get those dates on the calendar. I'd love to attend...

I am also going to try and do a texas meet this year.

LCHelilover

My Feedback: (15)

I haven't submitted my sanction request yet, but we try to have our contest two weeks before Crowley and two weeks after Frisco. It's the first or second weekend in October-depending on when the first of the month falls.

mjfrederick

Looking forward to seeing you again, Dean. Come on over, the water's fine! (And the food ain't bad either)

Patterndude1

Awsome Dean, you are finally able to come to our contest again . )) We will be glad to see you.

Thanks for the message and I think I am going to give Jason a call, I have his number in my cell phone.

Also George I am going to give you a call this afternoon reguarding our pattern contest.



Matt L.

Astropattern

My Integral was purchased one year ago and flown this past season. The manual says the CG should be at 205, but Jason subsequently suggests 190, and I currently fly mine at 150! This means that the CG is exactly on the nylon wing retaining bolt. I have the 170DZ, Hyde AR, and short pipe. I use two TP910 LiPos mounted just behind the landing gear and the Rx is up in the turtledeck behind the canopy along with two voltage regulators. I use the stock CF gear that came with the kit. I had originally put almost 4 ozs of lead in the tail but have removed all of it since then. The only mod I did to the plane was to put Gator stab adjusters in the tail because I thought the stock incidences were wrong, but in the end I am back to very close to stock. However, the plane still pulls to canopy on up and down lines, and moving the CG forward has reduced this quite a bit.
Structurally, I agree that the CF ending 4 inches ahead of the spar will make it fragile, but I think that to offset the fragility of the kev/balsa fuse to bring it to the same resilience as fibreglass would need CF all the way back to rear fuse. I have had both some harder landings and some "hangar abuse", and the plane doesn't seem to suffer too much.
I bought this plane as a replacement for the loss of a previous plane, and I was looking for the lowest cost ARF that had a reasonable track record. That is exactly what I got, and I can see that it has good performance. However, it is by far the most difficult plane to trim that I have ever owned.
You buy the meat, you buy the bones, as famous man once said...

John

(Pic of my plane at NSRCA D5 page)

jlkonn

My Feedback: (1)

John,
I gotta add...Your Integral is one of the best looking pattern planes I have ever seen.
You did a beautiful job inside and out!
[sm=thumbs_up.gif][sm=thumbs_up.gif]
JLK

papaone

Hi

Is this Integral ? Il est magnifique
Claude

jlkonn

My Feedback: (1)

Yes, that's John's Integral he talks about in post#18.
JLK

Astropattern

...And in reply to an off-line e-mail question...yes, I'd buy another one. (By that time, I'll have figured this one out)

John

patternflyer1

My Feedback: (11)

Doesn't moving the cg forward cause the plane to pull harder to the canopy in up and down lines as nose heavy makes you add up elevator trim.

Chris

Astropattern

You'd think so, but the problems are separate issues. I've got the CG in the right spot for inverted flight at this position, and it did help the pull to canopy a bit. The pull to canopy will be solved with reduction in wing incidence (currently +2), and then I'll have to find the right stab incidence (currently almost +4).

John

patternflyer1

My Feedback: (11)

Hmm, that's odd, Bryan told me just the opposite on the cg. That the nose heavy will make the plane carry more up trim, which will in turn fix a pull to the belly in knifes. And that more positive incidence in the wing will take care of the pull to the canopy in the up and downs. I just went through this same issue.

Nice plane though John.. And BTW, nice website D5!!!
Chris