KMP F-7F Tigercat
#2277
Hi Pete, You have probably seen my F7F on this site. It has SMOKE and has been flown for a few years at Air Shows. If you are TEST flying off a SHORT hard surface runway (600 Ft.) or something like that, you can end up with a lot of trouble. My Cat needs at least 800 Ft. to obtain enough ENERGY to lift off with full SAFE control. If you are using a grass field, be sure you don't try to PULL (Lift off) too soon. This airplane has VERY HIGH wing loading and needs SAFE takeoff speed. My first TEST flight was on a Full Scale Runway. I tell the story in one of my early posts. Chuck Winter Col. USAF (Ret.)
#2279
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Join Date: Jan 2004
Location: Bardufoss, NORWAY
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Mine takes off on its own after 15 m/50' and lands slowly on the first half of our <300' field with ditches around it. Your mileage may vary. Mine's 10,5 kg and the built up wing.
Last edited by tahustvedt; 11-26-2016 at 05:58 AM.
#2281
Hi Pete, My Cat is one of the original all fiberglass. I also strengthened the center section (See my center section FIX) in this F7F FORUM. My cat with the new Smoke installation (20 liquid oz. of. Smoke Oil at takeoff) weights 35 lbs. I do drop my Elevators about 2 Deg with full flaps and no degrees at halve flaps. I also DROOP/DROP my ailerons at about 10 degrees with full flaps. I also have a Rudder Gyro to give me some if necessary if I lose an engine. With the high wing loading of my CAT I need all the low speed lift I can get on landing. During my approach to landing I carry about 3/4 power to keep up the speed and if necessary for quick response for power if I need a Go - Around. If you go through this Forum on the F7F, you will read some horror stories about crashes on takeoffs and landings. This is a very impressive airplane in flight, but you MUST respect it. It's not a simple Run of the Mill model airplane. Don't test your CAT until you are totally satisfied with ALL SYSTEMS. Don't have lots of FRIENDS and HELPERS huddling over you while setting things up for flight. I want NO-BODY around when Im setting up. It's difficult at Air Shows when you have crowds of on-lookers and asking questions. GOOD LUCK with your MAIDEN FLIGHT. Col. Chuck Winter
#2286
My Feedback: (66)
For some with not much experience the droop will be a problem. If the get the plane to slow and then try to use ailerons during landing. Chuck is a good pilot and knows to keep his speed up. It always recommended to not drop the ailerons or to use your ailerons as flaps on some planes as it can led to a stalled wing tip.
#2287
Hi CAT FANS, I probably have more flights on my CAT than most CAT owners. I probably have more flights at Air Shows in front of hundreds of spectators. WATCH one of my complete flights at a LARGE AIR SHOW, go to Page 89 #2222 or if you want FULL SCREEN, go to YouTube and write in "rcgrummanf7ftigercatattheimaacastleflyin" ---- RC Grumman F7F Tigercat at the IMAA Castle Fly-In -- You can see FULL STABILIZED control with Gear Down, Full Flaps with Droop Ailerons. The touch down is right in front of me with a SMOOTH bounce under FULL CONTROL. I fly this airplane as if it is a FULL SIZE airplane similar to some that I flew in the USAF. I don't consider this as a MODEL AIRPLANE, it's a REAL AIRPLANE in MINIATURE. Throttle management thru the complete flight. In full size airplane ( I have flown Prop airplanes to Mach 2 Jets ) it's Called "Stored Energy" My last POINT, at my age 86, I have learned to follow and learn from SUCCESSFUL people. Enjoy your CAT and get to LOVE IT. Col. Chuck Winter USAF (Ret.)
#2288
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I've seen your videos, which are spectacular with the speed and smoke. You can probably land a lot slower than that though. My Tigercat is nothing to be afraid of, and if you don't droop your ailerons you don't have to keep the speed super high to keep control. Just drop flaps way down and keep power on to counter the drag and control descent with power like a normal plane. Inboard flaps also work as increased washout in a wing.
I'm just an aircraft technician.
I'm just an aircraft technician.
#2289
Hi ???? Not sure of your first name (tahustvedt) I had flown my Cat with only Flaps for over a year and tried 10% Droop Ailerons and liked the FEEL on landing. I don't use High Speed (SUPER HIGH SPEED) on landing. In the video you can see the landing is not FAST but very SAFE and controllable. Col. Chuck Winter
#2290
My Feedback: (13)
Hi CAT FANS, I probably have more flights on my CAT than most CAT owners. I probably have more flights at Air Shows in front of hundreds of spectators. WATCH one of my complete flights at a LARGE AIR SHOW, go to Page 89 #2222 or if you want FULL SCREEN, go to YouTube and write in "rcgrummanf7ftigercatattheimaacastleflyin" ---- RC Grumman F7F Tigercat at the IMAA Castle Fly-In -- You can see FULL STABILIZED control with Gear Down, Full Flaps with Droop Ailerons. The touch down is right in front of me with a SMOOTH bounce under FULL CONTROL. I fly this airplane as if it is a FULL SIZE airplane similar to some that I flew in the USAF. I don't consider this as a MODEL AIRPLANE, it's a REAL AIRPLANE in MINIATURE. Throttle management thru the complete flight. In full size airplane ( I have flown Prop airplanes to Mach 2 Jets ) it's Called "Stored Energy" My last POINT, at my age 86, I have learned to follow and learn from SUCCESSFUL people. Enjoy your CAT and get to LOVE IT. Col. Chuck Winter USAF (Ret.)
WOW flying(well) at 86.There is hope for all us old guys.
#2291
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Join Date: Jul 2002
Location: Gulf Coast
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Got my ESM F7F in December from VQ Warbirds and have read all 92 pages of this mostly informative thread.............thanks to all the constructive posters. Hope the thread continues on. ESM has incorporated a few changes for a few of their problems, but there is still plenty of rework for the craftsmen among us. Tomas at VQ Warbirds has done an outstanding job supporting this customer throughout the buying and follow on period.
Cheers - Boyd
AMA 80383
IRCHA 3553
LSF 853
Major USAF
Retired
Cheers - Boyd
AMA 80383
IRCHA 3553
LSF 853
Major USAF
Retired
#2292
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Join Date: Sep 2003
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Pete -
How did you do the electronic ignition setup in your Tcat? I have owned my for a few years now with a pair of Satio 1.80 engines. It flew quite well but I finally made the move and switching all my planes to gas engines. The Tcat will be my first gas twin powered plane (a pair of CRRC 26cc gas engines). Did you use one kill switch with a "Y" harness going to both ignition boxes? Did you use one battery per ignition box? I'm not sure what's the best way to set up a twin gas airplane. Any advice would help!
Keith
Retired U.S. Army - I miss flying the AH-1 Cobra!
How did you do the electronic ignition setup in your Tcat? I have owned my for a few years now with a pair of Satio 1.80 engines. It flew quite well but I finally made the move and switching all my planes to gas engines. The Tcat will be my first gas twin powered plane (a pair of CRRC 26cc gas engines). Did you use one kill switch with a "Y" harness going to both ignition boxes? Did you use one battery per ignition box? I'm not sure what's the best way to set up a twin gas airplane. Any advice would help!
Keith
Retired U.S. Army - I miss flying the AH-1 Cobra!
#2293
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Join Date: Nov 2005
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Hi All,
I just noticed that I had several PMs regarding the landing gear I have for the Tigercat. I used to get a notice when a new PM arrived, but haven't seen one in a long time. I still have the gear: Sierra Giant, with ESM wheels and tires, brakes and control valve. If anyone is still interested, please let me know. I'll send pics and details. I have no plans to build another TC, so I'm ready to deal!!
Thank you,
Nick
I just noticed that I had several PMs regarding the landing gear I have for the Tigercat. I used to get a notice when a new PM arrived, but haven't seen one in a long time. I still have the gear: Sierra Giant, with ESM wheels and tires, brakes and control valve. If anyone is still interested, please let me know. I'll send pics and details. I have no plans to build another TC, so I'm ready to deal!!
Thank you,
Nick
#2295
My Feedback: (85)
Pete -
How did you do the electronic ignition setup in your Tcat? I have owned my for a few years now with a pair of Satio 1.80 engines. It flew quite well but I finally made the move and switching all my planes to gas engines. The Tcat will be my first gas twin powered plane (a pair of CRRC 26cc gas engines). Did you use one kill switch with a "Y" harness going to both ignition boxes? Did you use one battery per ignition box? I'm not sure what's the best way to set up a twin gas airplane. Any advice would help!
Keith
Retired U.S. Army - I miss flying the AH-1 Cobra!
How did you do the electronic ignition setup in your Tcat? I have owned my for a few years now with a pair of Satio 1.80 engines. It flew quite well but I finally made the move and switching all my planes to gas engines. The Tcat will be my first gas twin powered plane (a pair of CRRC 26cc gas engines). Did you use one kill switch with a "Y" harness going to both ignition boxes? Did you use one battery per ignition box? I'm not sure what's the best way to set up a twin gas airplane. Any advice would help!
Keith
Retired U.S. Army - I miss flying the AH-1 Cobra!
I used two kill switches one in each nacelle connected with a Y cord to a single channel to kill the engines. I thought it was important to see when each engine is "Hot" with the LED on each nacelle as in the photo. Also the 4.8v NiMh pack is mounted in each nacelle just behind the former. Also upgraded to Sullivan 16 oz tanks with 3 lines (Carb,Fill,Vent). They fit perfectly.
Also I changed out all the 3mm control horn bolts for the ailerons and flaps. Within two weeks of setting up , running engines and taxi testing an aileron and flap bolt sheered off at the base. I installed Dubro HD adjustable control horns for 0.91 and above. They went in great but I had to shorten the flag piece on the bolt that accepts the clevis and drill a new hole in it. This was too long and put the pivot point ahead of the hinge line.
I hope to maiden mine this weekend as the weather looks good here in East LA.
Pete
#2296
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Hi Gentlemen,
I just ordered from Tomas @ VQ an F7F with Sierra retracts. He worked with me on the shipping to Hawaii and a good man to deal with.
I have two DLE 20's new for this model and after reading part of this thread...realized most the folks used 26cc gas engines or larger to fly the model.
I need to know if I will need larger engines to power this model. The last thing I want is an underpowered model and one that is as beautiful as this is.
Any one out there flying this model with 20 cc gas engines?
I need to know the consensus of you guys...so chip in and let me know what you feel is the best power plant for this model.
Soft Landings Always,
Bobby of Maui
I just ordered from Tomas @ VQ an F7F with Sierra retracts. He worked with me on the shipping to Hawaii and a good man to deal with.
I have two DLE 20's new for this model and after reading part of this thread...realized most the folks used 26cc gas engines or larger to fly the model.
I need to know if I will need larger engines to power this model. The last thing I want is an underpowered model and one that is as beautiful as this is.
Any one out there flying this model with 20 cc gas engines?
I need to know the consensus of you guys...so chip in and let me know what you feel is the best power plant for this model.
Soft Landings Always,
Bobby of Maui
Last edited by Bob Paris; 01-29-2017 at 02:00 AM.
#2297
My Feedback: (4)
Bobby,
I copied and pasted an early post I made below regarding the DLE's. I flew it several times after I re-engined it with the G-26's but didn't find much difference. What I didn't mention in post below is that most of the time I flew at full throttle. Anything less and plane wasn't very fast. I suspect the weight might be the reason. seemed to me it was 30-32 pounds. I'm going to try DLE 30's next. Have had better luck with them on another plane than the 20's.
I have one of these that I put together 2 years ago. I used DLE 20's and have since removed them and am in the process of installing Zenoah G-26's. The DLE's flew the plane nicely, fast enough to be fun. I had trouble out of the box getting the left one (DLE) to run. Sent it back to Tower and they sent me a new one, no explanation why it wouldn't run. It ran good out of the box and I flew it in another plane to break it in. Then I installed it in the Tigercat and set it to run with the other engine, slow and high throttle. Flew plane 2 or 3 times. Next flight, I started both engines and let them warm up. throttled up to check high end and watched the left prop come flying off. What the ___! Engine seized up solid. Another 30 seconds later I would have been lifting off and watched it destroy itself. Sent that engine back to Tower and they sent me another new one. No explanation on this one either.That one went on E-Bay as did the right engine. I used quality oil and Non-ethanol fuel. No more DLE's for me. In case any ones thinking of these engines, and I know there are enough of these engines out there that run, I wouldn't risk a twin again with one. My 2cents.
Keith
I copied and pasted an early post I made below regarding the DLE's. I flew it several times after I re-engined it with the G-26's but didn't find much difference. What I didn't mention in post below is that most of the time I flew at full throttle. Anything less and plane wasn't very fast. I suspect the weight might be the reason. seemed to me it was 30-32 pounds. I'm going to try DLE 30's next. Have had better luck with them on another plane than the 20's.
I have one of these that I put together 2 years ago. I used DLE 20's and have since removed them and am in the process of installing Zenoah G-26's. The DLE's flew the plane nicely, fast enough to be fun. I had trouble out of the box getting the left one (DLE) to run. Sent it back to Tower and they sent me a new one, no explanation why it wouldn't run. It ran good out of the box and I flew it in another plane to break it in. Then I installed it in the Tigercat and set it to run with the other engine, slow and high throttle. Flew plane 2 or 3 times. Next flight, I started both engines and let them warm up. throttled up to check high end and watched the left prop come flying off. What the ___! Engine seized up solid. Another 30 seconds later I would have been lifting off and watched it destroy itself. Sent that engine back to Tower and they sent me another new one. No explanation on this one either.That one went on E-Bay as did the right engine. I used quality oil and Non-ethanol fuel. No more DLE's for me. In case any ones thinking of these engines, and I know there are enough of these engines out there that run, I wouldn't risk a twin again with one. My 2cents.
Keith
#2298
My Feedback: (13)
Hay Keith,
I have run a DLE 20 RA in a T.F. .60~.90 P-51D and its been a great running engine. Lots of power for the model and it came in a tad over 10#'s. With a model at 30~35#'s...maybe I should rethink the DLE 20's. The DLE 20 RA's are not the same as your first DLE's sold several years ago. For the first DLE's had carb issues and several guys in the club were not to fond of them. I flew RGCF 20cc engines and to me...I was really happy with them. No carb issues...lots of power and love the engines. Not many guys talk about RGCF engines...but they were good easy starting and dependable engines. I purchased these two engines with rear exhaust...and one counter rotating for a P-38 project...but now have this F7F to power.
Will a twin cylinder 30cc RGCG fit into the cowls...? It is 9.25" wide, weight 2.53 #'s. If these will fit...I will go with two of these.
I did go with Sierra retracts and I had a set in an ESM F6F. I was pleasantly surprised at how robust they were...and took all I gave them and just worked. They do take a bit more air to operate...but the air cylinders are the largest installed on any retract their size. Solid...very well built...and never failed me. I went with the Robert auto-lower unit and it worked as advertised.
Soft Landings Always,
Bobby of Maui
Soft Landings Always,
Bobby of Maui
I have run a DLE 20 RA in a T.F. .60~.90 P-51D and its been a great running engine. Lots of power for the model and it came in a tad over 10#'s. With a model at 30~35#'s...maybe I should rethink the DLE 20's. The DLE 20 RA's are not the same as your first DLE's sold several years ago. For the first DLE's had carb issues and several guys in the club were not to fond of them. I flew RGCF 20cc engines and to me...I was really happy with them. No carb issues...lots of power and love the engines. Not many guys talk about RGCF engines...but they were good easy starting and dependable engines. I purchased these two engines with rear exhaust...and one counter rotating for a P-38 project...but now have this F7F to power.
Will a twin cylinder 30cc RGCG fit into the cowls...? It is 9.25" wide, weight 2.53 #'s. If these will fit...I will go with two of these.
I did go with Sierra retracts and I had a set in an ESM F6F. I was pleasantly surprised at how robust they were...and took all I gave them and just worked. They do take a bit more air to operate...but the air cylinders are the largest installed on any retract their size. Solid...very well built...and never failed me. I went with the Robert auto-lower unit and it worked as advertised.
Soft Landings Always,
Bobby of Maui
Soft Landings Always,
Bobby of Maui
Last edited by Bob Paris; 01-29-2017 at 02:11 AM.
#2299
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How about the Evolution 33gx ??? anyone try those??
Lightweight //// compact....
http://www.horizonhobby.com/33gx-33c...ngine-evoe33gx
Just adding some ideas for consideration....
Lightweight //// compact....
http://www.horizonhobby.com/33gx-33c...ngine-evoe33gx
Just adding some ideas for consideration....
#2300
Hi Bobby,
The weight of your Tigercat is what will determine the engines you choose. My Tigercat weights 34 lbs with 20 oz.of Smoke Oil at Takeoff weight. I'm flying with 2 FUJI 23s and they are JUST adequate power. My takeoff rolls are long and I need a little more than 1/2 throttle to maintain level flight. With gear and flaps down I need 3/4 power and sometimes full power. I think the DLE 20s will be ON THE SMALL size. Enjoy your Tigercat. Col. Chuck Winter
The weight of your Tigercat is what will determine the engines you choose. My Tigercat weights 34 lbs with 20 oz.of Smoke Oil at Takeoff weight. I'm flying with 2 FUJI 23s and they are JUST adequate power. My takeoff rolls are long and I need a little more than 1/2 throttle to maintain level flight. With gear and flaps down I need 3/4 power and sometimes full power. I think the DLE 20s will be ON THE SMALL size. Enjoy your Tigercat. Col. Chuck Winter
Last edited by CHARLES WINTER; 01-28-2017 at 11:40 PM. Reason: Needed more pictures