I have purchased and assembled the airframe, but not yet flown it.

Did your CG really come out to 95mm behind the leading edge using a 3s 2200 mAh without
doing anything special?

Mine is off by a considerable margin - FMS is responsive, but so far, not helpful.

Adding weight to a brand new ARF airframe is just a crime against nature.

Advice?

Alan

Originally Posted by Alan999

I have purchased and assembled the airframe, but not yet flown it.

Did your CG really come out to 95mm behind the leading edge using a 3s 2200 mAh without
doing anything special?

Mine is off by a considerable margin - FMS is responsive, but so far, not helpful.

Adding weight to a brand new ARF airframe is just a crime against nature.

Advice?

Alan

Finally had a chance to fly today - still a little windy, so fine tuning not possible.

After several iternations with FMS, they offered that 110mm CG is OK, though they still reccomend 95MM.

110mm CG meant only about an ounce of nose weight - still more than I'd like, but not terrible.

When I fly it, my CG test is to set a 45 degree up line - roll to inverted - then hands off all controls for a couple of seconds and see what the airframe does.

The airframe gently fell off the 45 degree upline, without going left or right.

This is just about right.

flying inverted on the level, a bit of up elevator makes it track nicely.

Too windy with gusts to do more fine tuning, but the key takeaway here is

CG = 110 mm is OK

My Explorers fly well at CoG of 125mm. Stock battery position, 2200 mah 25C 3S.
These planes always amaze me with their precise, smooth and gentle flying characteristics. Like others have posted, can do anything I want and can do, and a lot more for sure. Never does it lack for power even with extended vertical uplines to out of sight.

I dont have bigger F3A planes, but have seen them. I think in the hands of a good pilot, the Explorer will place well in a lower class F3A contest.

BTW, I use an EMP 11x7E propeller and get way better performance than the stock 11x5.5 APC clone. EMP props have been tested to perform better than equivalent brand "A" props.

I upgraded the motor/esc in one Explorer with a Turnigy 3536 1250 KV and 70A esc. I am giggling like a schoolgirl throughout every flight. So much fun. Lands at a crawl and easily does 80 mph. (estimated). From standing start, takes off in 10 ft then goes vertical literally out of sight.

This and the ROC Hobby Critical Mass are my two favorite 1100mm planes to fly.

Originally Posted by Alan999

Finally had a chance to fly today - still a little windy, so fine tuning not possible.

After several iternations with FMS, they offered that 110mm CG is OK, though they still reccomend 95MM.

110mm CG meant only about an ounce of nose weight - still more than I'd like, but not terrible.

When I fly it, my CG test is to set a 45 degree up line - roll to inverted - then hands off all controls for a couple of seconds and see what the airframe does.

The airframe gently fell off the 45 degree upline, without going left or right.

This is just about right.

flying inverted on the level, a bit of up elevator makes it track nicely.

Too windy with gusts to do more fine tuning, but the key takeaway here is

CG = 110 mm is OK

Hi Alan,
It's me, Mike! I enjoyed watching you fly the Explorer yesterday, it looks like a great plane with smooth flight characteristics. It'll be nice to see once you finish the fine tuning.

This little plane seems to track well, but how does it spin and snap?

Originally Posted by HansL

This little plane seems to track well, but how does it spin and snap?

Depends how you set up control throws.

Mine are set for smooth flying, although it can do about 1.5 axial aileron rolls per second at full stick. So I normally roll at half stick. All my controls are at 25% expo. Outermost hole on servo arms and nearest (to hinge) on control horns.

Given this set-up, snaps are gentle and full stall spins are both about 1 per second

If I set controls to maximum throw on servo arms and control horns, snaps and spins should be faster. Then I'd probably need to use low rate on d/r for normal flying.

Originally Posted by Rogue_Pilot

Hi Alan,
It's me, Mike! I enjoyed watching you fly the Explorer yesterday, it looks like a great plane with smooth flight characteristics. It'll be nice to see once you finish the fine tuning.

Thanks for the kind words Mike

Based on the (greatly appreciated) inputs from EasyRider604, I'd like to
slowly test a CG that is further back - and pull some of that extra ounce out of the nose.

Some days with a bit less wind will come soon, then we shall see.

Does anyone know where to set the motor thrust? my F3A Explorer CG is set to 115mm. With the elevator set to the center of the stab, I have to hold an excessive amount of up elevator to fly straight and level. The plane's down line with motor at idle is straight, but in the up line with 2/3 to full throttle the plane pitches to the belly. I believe I need to add motor up thrust to correct this problem. Has anyone else experienced this issue? Does anyone know where the motor thrust should be set?

Alan999, did you test the CG further back from 110mm? What was the result, did the plane fly better? Were there any cross couple issues? Per your testing, what CG location do you believe is best?

Originally Posted by flyinbill1

Does anyone know where to set the motor thrust? my F3A Explorer CG is set to 115mm. With the elevator set to the center of the stab, I have to hold an excessive amount of up elevator to fly straight and level. The plane's down line with motor at idle is straight, but in the up line with 2/3 to full throttle the plane pitches to the belly. I believe I need to add motor up thrust to correct this problem. Has anyone else experienced this issue? Does anyone know where the motor thrust should be set?

I adjusted the downthrust to look like the picture, by inserting thin washers under the bottom arms of the the motor cross mount.

Other picture shows the CoG (BMW-like sticker) is at 125mm back from leading edge, at the wing root. Note Battery location and no weights added anywhere at all.

My motor is a powerful Hobbyking 1250KV Turnigy 3536 and prop is EMP 11X7E. I am probably drawing more than 40 amps so upgraded to a 70A ESC borrowed from a FMS 980mm P47.

When trimmed to fly straight and level at full throttle, I can cut throttle to 3/4 and still fly straight and level with no elevator trim necessary. This is how I like to set up my planes. It is very easy to turn as she needs minimal elevator back pressure. This makes it a very easy plane to fly and land

Inverted flying is also very relaxing as hardly. any down elevator is required for level flight.

The Explorer can actually turn with rudder only, BTW.

Thanks easyrider604. That helps greatly and the photos are exactly what I needed to see. I'll give it a try.

Originally Posted by flyinbill1

Alan999, did you test the CG further back from 110mm? What was the result, did the plane fly better? Were there any cross couple issues? Per your testing, what CG location do you believe is best?

Sorry for the slow response.

Yes, My problems are now pretty well sorted out.

After multiple flights, I have now removed ALL extra nose weight - flying with a 2200mah 3s either all the way forward or middle of the tray. Inverted in level flight, it takes just a touch of down elevator.

I have not actually measured the CG - I can do so if someone needs the info.

I fly for pretty rough grass strips - long grass and sometimes bumpy ground - the Landing Gear were always leaving me with the spinner rather than the tail wheel as the 3rd support point, no matter how smooth the landing.
I removed the wheel pants, which helped but did not totally solve the problem - then I realized I could simply reverse the LG, which moves the wheels about an inch farther forward from the CG, works pretty well now.

Flying experiences are similar to others on this forum. Like full scale aerobatic planes, it does not have unlimited vertical power (like my 3D stuff) so some
planning about conservation of energy in big vertical manuevers is required. Not a problem, just different.

Really flies best when the airspeed is in the top 1/3 of the throttle - can rapidly lose lots of altitude when there is a bobble at low airspeeds.

Behaves pretty well - still working on long passes in knife edge - it can be done, but requires some concentration and precision.

Getting 5 1/2 minutes with 30% of the battery left

Handles moderate winds pretty well, as long as they are steady (not gusty)

Overall, pretty happy with the product now - once past the confusion of mfg CG info that (at least for me) was not very accurate. If in doubt, fly it and adjust.

Considering buying the F3A Explorer but curious about the quality of the electronics included in the PMP package. Are the servos digital? Metal Gears? any problems with them or any of the other electronics.

Trying to decide between this plane and eflite Leader 480.....


Thanks for your recommendations !!!

Originally Posted by squigintx

Considering buying the F3A Explorer but curious about the quality of the electronics included in the PMP package. Are the servos digital? Metal Gears? any problems with them or any of the other electronics.

Trying to decide between this plane and eflite Leader 480.....


Thanks for your recommendations !!!

These two are apples and oranges.

Explorer is a foamie PNP with a very current design including the "canalizer" mini wing. I am flying two Explorers and have an extra one unassembled on the shelf. The servos are 9 gram analog plastic geared, the motors and ESCs are just the usual garden variety units or types that FMS puts in practically all its models. After dozens of flights, the electronics have been reliable so far. Similar servos in my FMS 800mm T28 have 150 flights with no issues.

Leader is a balsa ARF with conventional pattern design. You install electronic and electric components of your choice. You can put in cheap or high end components.

I have not flown the Leader, but in videos, its performance is old school pattern. In today's world, its a good all around sport flier, IMO.

The Explorer is a modern design and it flies like the big 2 meter F3A ships, only in a smaller handier package. Explorer is a great platform for F3A training, IMO. The little canalizer wing increases wing area, like a biplane does. It allows the main wing to be shorter making response to lateral control very quick and precise. Much like the modern Pitts biplanes. Rolls are axial and controls are very precise so 4-pointers and slow rolls are easy.

The fuselage profile allows for endless Knife Edge. It can turn flat or make circles amd horizontal 8s with Rudder only. When Explorer is set up properly with expo and correct CoG it is truly a joy to fly. Inverted is a snap. I replaced the prop with an 11x7 EMP on one Explorer.

The other Explorer is a monster after I replaced the motor with a Turnigy 3536 1250KV with 70A ESC from the ROC Hobby 980mm Thunderbolt, also 11x7 EMP prop. Both can do unlimited vertical, but with the 1250KV motor, its verticals are spectacular. With a short 10 foot take off run, the 1250KV motor equipped Explorer can pull up into a rolling unlimited vertical climb to out of sight.

Explorer has wide flight envelope. It can slowdown to a nose high tail wheel first landing. It has enough speed and momentum for most if not all the most difficult F3A maneuvers.

easyrider604
Are your cg's still at the 5 inch, 125mm point? Thanx