aerofart

Nice thread here, guys. I've learned a great deal.

I have a modified GP Lancair ES EP. I've swapped out the included inrunner and power pack with a Park 400 outrunner (920Kv, 1:1) which fits near perfectly. I also am using a 3S 1250ma LiPo pack and brushless ESC. The only other mod is the addition of some right and down thrust mounting angle.

Prior to shimming up the motor for the thrust angle, I had been taxiing the plane. It rolled down the street straight and stable at low power, so I decided to see what would happen when I applied full power for a short burst. As I expected, when ample power was applied, the plane would veer sharply to the left - rather disconcerting.

I've considered applying right-rudder/nosegear during rollout in order to counter the "torque" effect, but the travel on the rudder/nosegear is at max throw (just slightly under what is recommended in the instruction manual), which makes for way-too-sensitive nosegear control at higher speeds.

As an alternative, I decided to shim the motor for right/down thrust. This has nearly eliminated the veering at higher rollouts down the runway (street). I am concerned, however, that angling the motor may have some adverse effects that I am not currently able to predict/foresee. The instructions make no mention of thrust angle adjustments, but then again, with the underpowered system they recommend, its no wonder they don't worry about it.

So I need the advice of those wise enough to know better. Do I leave the thrust adjustment in, or mount the motor true to the firewall???

I believe I have lots of power and a probably very close to The Specs on wing-loading, since using the brushless and LiPo. Also, I've had to add a chunk of lead in the engine cowl to get the CG to 2" from the wing leading edge. Is it a good idea to add my ballast inside the engine cowl? I wanted to get the weight as far foreward as possible to minimize wing-loading.

How much runway does the Lancair need to get off the ground with my setup?

Photos attached . . . although they were taken prior to thrust-angle mounting adjustments (just alumin shimming running along the left side and sandwiched between the mounting plate and firewall).

Thanks!

wb2fka

Try http://www.rcgroups.com/forums/showt...468746&page=76. You will find an up-to-date discussion of the GP Lancair EP. Those guys can probably answer your questions.

Chillybee

My Feedback: (3)

I've replaced my stock motor with an ElectriFly Ammo 20-40 4850kv. Since the motor shaft is around 10.5mm, I needed a long pinion gear~10 mm to reach the main gear through the firewall. But I can't seem to keep it perfectly straight after tightening the set screw eventhough the hole is 2mm just like the shaft. Therefore, the distance between the 2 gears constantly changes and my plastic main gear is fried. Has anyone tried other gear boxes for the Lancair or does anyone have any suggestion how to keep the pinion gear true with the shaft?

Orlando

hsadi

I have a Great Planes Lancair EP,
I am planning to use brushless engine. Which engine I should to use.

wb2fka

I wrote a post which appears on page 6 of this thread describing the replacement brushless motor that I used from MileHighRC.com which directly replaces the toy motor supplied with the plane. However, if I had to do it all over again, I'd use a direct drive motor and discard the junky gearbox. It's too high maintenance! Since it is such a beautiful model, I would have gladly paid the same money for it if it were designed to accept high performance components of my choosing without the included useless drive and power supply components that are now taking up space in a parts box in my basement. []

geeter

My Feedback: (110)

has anyone tried putting a nitro eng in the lancair ep ? seems a os .15 or magum .15 would work well. a motor mount could be fabbed of alum, and a 4 oz tank could be fit in there. be better than going brushless and finding a motor and doing away with the gear drive that strips out. besides all the li-po's and charger,plus a brushless speed control,seems like a waste over a small nitro motor that sure wouldn't burn much fuel and wouldn't be any heaver either. what do you think?............RON

jonan

Aerofart - Whew! Just the info for which I was searching. I recently bought a Lancair ES, and can't get it off of the runway with the provided power system. Was trying to figure out what to do next. Your solution looks really good, especially the set up with the motor. I'll keep looking for your experience with the airplane. Jonan

jonan

Aerofart - I need to do the same thing to my Lancair ES that you did to yours. How do get the motor shaft to line up with the cowling? Also, did you use the original mount that was for the T-400? Anything more on the installation of the Park 400 to the Lancair would be helpful. Thanks, Jonan

tkopper

Hi, I have this airplane, its very nice; does anyone know what brushless motor would work well in this plane without using a gear box?, I want a direct drive setup for the lancair ep. Thanks, Tom

redriderjt

Just bought this plane aswell.. looking to make it brushless too. wanting to know what kinda preformace people are getting out of these thing in brushless configuration..

wb2fka

I first converted the Lancair to outrunner brushless using a motor from milehighrc.com that directly replaced the toy brushed motor that Great Planes supplied. Initially, it worked fine. Unfortunately, the gearbox didn't hold up because it was of the same poor quality as the original brushed motor. I then converted the plane to direct outrunner brushless drive using a 900 KV outrunner brushless motor from milehighrc.com. In order to retain the same positioning of the motor prop shaft in the cowl opening as the original gearbox prop shaft, I had to cut out a large opening in the firewall and make an elaborate custom motor mount. Because the brushless motor is so much lighter than the old toy brushed motor and gearbox, I had to do extensive modifications to secure the LiPo battery forward enough in the fuselage to achieve the correct CG. Although it finally worked out and the plane flies very well, I wouldn't want my worst enemy to repeat what I went through.There have been a number of extensive threads on the Internet describing brushless motor installations for this model that required cutting off the existing firewall and installing a new plywood firewall. Unfortunately, I can't find them anymore. In addition to the redesign of the motor installation, I had to design a front pin and rear lockdown screw arrangement to hold the canopy on securely. If I knew what I was in for, I would not have undertaken this project even though the the Lancair is a beautiful model. There are too many great electric models out there that were designed to use modern brushless motor/LiPo battery drive systems and go together without all of the headaches of the Lancair EP. Check out www.airborne-models.com.

Below is a URL of a thread describing the installation of a brushless motor on the original Lancair EP firewall. The author enlarged the opening in the cowl to permit the front of the motor to poke through.

http://www.wattflyer.com/forums/show...ght=Lancair+ES

wb2fka

[8D]OK guys, I found the threads on the Lancair EP. They're listed below. Good Luck!

http://www.rcgroups.com/forums/showthread.php?t=468746

http://www.wattflyer.com/forums/show...hlight=Lancair

http://www.rcuniverse.com/forum/m_35...Lancair/tm.htm

redriderjt

anybody flying this bird on the stock set up?? if so hows the stock drive gear holding up?? I have an old ammo inrunner thats the same size as the stock motor thinking about just bolting that in.. Just wondering is the reduction gear drive can handle it..

wb2fka

The biggest problem with the stock setup is the batteries. Switching to LiPo will make a big difference. The gear drive is not rugged. I replaced the original toy motor with a brushless motor and the gear drive didn't last very long. I installed a direct drive brushless motor, but that required major firewall modifications. Because the stock setup weighed so much, I had to squeeze the LiPo batteries as far up into the front of the fuselage as possible to achieve the correct CG without having to add lead in the nose. If I were you, I would start slowly by substituting LiPo's for the original batteries and see if that makes the plane flyable. With a brushless direct drive motor and LiPo batteries, the plane is a joy to fly. However, you've got lots of work ahead of you if you pursue that approach. Check out the following links before you do anything:
http://www.rcgroups.com/forums/showthread.php?t=468746

http://www.wattflyer.com/forums/show...hlight=Lancair

http://www.rcuniverse.com/forum/m_35...Lancair/tm.htm

http://www.wattflyer.com/forums/show...ght=Lancair+ES