Twin & Multi Engine RC Aircraft Discuss the ins & outs of building & flying multi engine rc aircraft here.

Super Sportster twin, short flight...

Reply
Old 08-01-2010, 04:45 AM
  #1
Fastsky
Thread Starter
 
Fastsky's Avatar
 
Join Date: Dec 2001
Location: Calgary, AB, CANADA
Posts: 2,985
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Super Sportster twin, short flight...

Well it took 3 tries to get the plane off the ground. The first 2 times I wasn't holding up enough up elevator to maintain control and the 2 OS 32s were almost pulling the nose of the plane over. The 3d time the plane blasted straight down the run way and took off very smoothly. I needed a bit of right aileron trim and then it was controlling nicely. I had APC 10-5 props and the plane was still plenty fast. I made a few rolls and the twin smoke trails looked really cool. Now the bad part; tried slowing it down and it got really mushy on the controls. It became very obvious that this plane has a very high wing loading! Made 3 rounds of the circuit trying to get lined up for the run way when the left engine died. It seemed to fly ok for about 5 seconds so I left the throttle on. Bad mistake!! Once the plane slowed down the torque from the right engine rolled it over and it went straight down from about 50 feet. The nose up to the canopy was totaled. The wing is fully intact except for 2 rips in the covering. No broken props! I had the timer running and I had a 5 1/2 minute flight. It was about 5 minutes longer than I expected so I'm happy! Based on the wing loading of this pig however I don't think its worth rebuilding. It flies awesome but it would be almost impossible to land it safely at my experience level. At least I flew a twin!
Fastsky is offline  
Reply With Quote
Old 08-01-2010, 11:42 AM
  #2
aerowoof
 
Join Date: Jun 2006
Location: pembroke, NH
Posts: 2,891
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Super Sportster twin, short flight...

sounds like it was more nose heavy than anything.twins always have a higher wing loading than a single especially scale.it wasn't torque that caused the roll but the drag of the dead engine and prop
aerowoof is offline  
Reply With Quote
Old 08-01-2010, 09:43 PM
  #3
Fastsky
Thread Starter
 
Fastsky's Avatar
 
Join Date: Dec 2001
Location: Calgary, AB, CANADA
Posts: 2,985
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Super Sportster twin, short flight...

Nose heavy planes haven't given me problems in the past but twins are a whole different king of animal. I ordered the plans for a Gemini from RCM. Its a high wing twin with a larger wing and more wing area. Might make a better choice for starting out than the comparitivly stubby Super Sportster. [8D]
Attached Thumbnails
Click image for larger version

Name:	Ay73747.jpg
Views:	34
Size:	28.7 KB
ID:	1476753  
Fastsky is offline  
Reply With Quote
Old 08-02-2010, 01:38 AM
  #4
aa1a
 
Join Date: Jun 2005
Location: Northern, CA
Posts: 131
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Super Sportster twin, short flight...

Sorry to hear of your problems with the sportster twin. I agree that it may have been nose heavy. Mine required tons of weight on the tail. I have about 10 flights on mine now. It handles great and tears up the sky with 2 os 55axs. Keep the speed up and it lands super easy. I got a little single engine practice the other day and it flew fine with one engine at 1/2 throttle. It was a lot of work but I'd build another one.
Jim
Attached Thumbnails
Click image for larger version

Name:	Qo40345.jpg
Views:	38
Size:	92.6 KB
ID:	1476847   Click image for larger version

Name:	Pk31891.jpg
Views:	29
Size:	46.3 KB
ID:	1476848   Click image for larger version

Name:	Fk16394.jpg
Views:	32
Size:	41.8 KB
ID:	1476849  
aa1a is offline  
Reply With Quote
Old 08-02-2010, 03:56 AM
  #5
Smoky
 
Smoky's Avatar
 
Join Date: Jul 2003
Location: Meadow Lake, SK, CANADA
Posts: 199
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Super Sportster twin, short flight...

Sorry to hear about your plane.

One thing to remember about a twin, when an engine stops, the Prop is no longer pulling and blowing air under the wing, instead it acts like a brake.
The Dead side will drop a bit instantly,due to lost airflow over the wing, and the dead prop will act like a brake causing that side to start to trail, thus you go inverted and spin in.
Typically if your speed is up, then you have enouogh airflow over the rudder to compensate and you can land it on one engine. LOW and Slow is the combination you never want! if it happens and you are low and slow, the best thing to do is idle the running engine and keep the nose slightly down and land it level.

Also a twin will typically drop pretty fast when you slow down the engines. So always land with a little power on. Don't try to float it in, fly it in. until just above the runway then cut and flair a bit.
hope this helps.
Smoky
Smoky is offline  
Reply With Quote
Old 08-18-2010, 05:58 PM
  #6
kakariki
 
Join Date: Jul 2010
Location: MorningtonVictoria, AUSTRALIA
Posts: 73
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Super Sportster twin, short flight...

Hi All
Just wonering where you can get the Gemini and Super Sportster Twin from.
Thanks Barry
kakariki is offline  
Reply With Quote
Old 08-19-2010, 12:50 AM
  #7
aa1a
 
Join Date: Jun 2005
Location: Northern, CA
Posts: 131
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Super Sportster twin, short flight...

If you want a Sportster twin you have to work for it. Buy a sportster 40 kit. They were recently discontinued but there are lots of them around. Buy the conversion plans from RC Modeler plans service. The magazine is long gone but the plans service remains. The plans have a list of additional required items. I got all the balsa and plywood items needed for about $50 from Balsa USA. Then start building.
Jim
aa1a is offline  
Reply With Quote
Old 08-24-2010, 08:59 PM
  #8
Robtck
 
Join Date: Jun 2003
Location: Sharpsburg, GA
Posts: 133
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Super Sportster twin, short flight...

I have a Super Sportster 60 Twin that flys great on OS 55AX engines(when both are running). It's flys ok on one engine at 1/2 throttle, above 1/2 throttle the rudder loses the battle. I added one inch to the leading edge of the rudder, but it still needs a bigger rudder or a longer tail. I also added a 11" center wing section. I did use the RCM SS40 twin plans as a guide when building mine.

Pictures 1&2 are after the first flight. Low and slow single engine.
Picture 3 The new outboard right wing panel installed and ready for covering.
Pictures 4&5 After 4 flights still airworthy.

Three out of the four flights ended in single engine ops. The left tank was a problem and now seems to be working fine after being rebuilt.
Attached Thumbnails
Click image for larger version

Name:	Nl31077.jpg
Views:	45
Size:	204.3 KB
ID:	1489948   Click image for larger version

Name:	Fa86434.jpg
Views:	28
Size:	215.9 KB
ID:	1489949   Click image for larger version

Name:	If10677.jpg
Views:	26
Size:	69.2 KB
ID:	1489950   Click image for larger version

Name:	Cx76837.jpg
Views:	31
Size:	187.4 KB
ID:	1489951   Click image for larger version

Name:	Yd82008.jpg
Views:	28
Size:	175.6 KB
ID:	1489952  

Robtck is offline  
Reply With Quote
Old 09-20-2010, 01:25 AM
  #9
Smoky
 
Smoky's Avatar
 
Join Date: Jul 2003
Location: Meadow Lake, SK, CANADA
Posts: 199
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Super Sportster twin, short flight...

fastsky: nice plane!
twinman used to say, once you fly a twin nothing else will satisfy your knee knock factor,, or something like that. i agree with him. the sound alone gets me grinning.
Don't get bored and hover it!! I did that with a twinstar and lost an engine at 50 ft. It didn't have a chance.[X(] Now i use the skybolt for stunts and the twin for fast level or fast inverted or fast vertical,, anything goes as long as it is fast! LOL.
happy flights.
Smoky is offline  
Reply With Quote
Reply


Thread Tools
Search this Thread
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -8. The time now is 02:44 AM.