RLefebvre

My Feedback: (1)

FWIW, my VMAR flew great with a ThunderTiger 46 Pro. Had tons of power and flew pretty quick. I wouldn't say it had unlimited vertical, but it was perfectly capable of loops, etc. Take off acceleration was great, good climbout, etc...

No, it wouldn't hover... But other than that.

I also found the stall to be quite gentle. The experienced guy who took it up showed you could fly at about 1/4 throttle with full (low rate) elevator up almost indefinitely. If you cut the power back, it mushed forward almost like a trainer.

sigrun

A word of CAUTION for those thinking about buying a PC-9 ARF who might easily be miguided by disinformation.

From a nonsense recently posted here, you might be misled into thinking of VMAR's PC-9 as pretty much the same as the Seagull PC-9, just produced by another manufacturer available in an alternative more appealing colour scheme. I've flown both in numerous test flights for others, as well as extensively operationally. No question, they both look great in the air, and VMAR offer their model in a number of alternative guises. I liked the way the Seagull unit flies so much, I bought another and currently have two operational. The VMAR unit however is a very different kettle of fish. It has several inherent design flaws which induce handling characteristics invariably proving fatal in the hands of the novice or your 'aerodynamically challenged' average R/C pilot.

Seagull's PC-9 weighs 2.7kg dry fitted with a typical .46 engine such as a TT Pro46 or OS 46SF/FX/AX. It has washout, generous wing area and section. It's speed capability notwithstanding, it is as viceless as any R/C model of its class can ever be.

OTOH VMAR's PC-9 weighs in at a whopping 3.0kg +, and 3.3kg + when fitted with a typical .61! It ain't going anywhere worthwhile with your average .46. It has a notably smaller wing than the Seagull in chord, span and section, and a sharply double tapered outer wing of diminishing section with insignificant washout. Overshooting on that late turn onto finals? Increase the AoB or tighten the turn applying a tad too much 'g' or reduce that power just a notch on short final to adjust ROD at an attitude and speed that offer zero visual clue of being anywhere near stalling angle or sufficiently slow for control to be an issue, and your VMAR PC-9 will dynamically stall at the tip and roll violently onto its back without warning in a heartbeat. Hence so many of them written off in crashes on (landing) approach.

Figure it out for yourself. With a considerably higher wing loading and an outer section prone to stalling both early and easily, this model does NOT "mush forward almost like a trainer" at the stall. In fact, VMAR's PC-9 is the only R/C model I've flown that will drop a wing so dynamically without pilot inducement off a clean non-dynamic stall entry and, almost unbelievably, auto-rotate into a stable spin without any rudder or aileron input from the pilot! As long as you keep that wing stalled with elevator, she'll keep spinning! At the stall intentionally induced or otherwise, this model will alway stall at the tip first and drop a wing. Recovery requires the wing to be positively unstalled with (elevator) which is accompanied by a momentary inertial delay whilst you get the wing accelerating and producing sufficient lift. If you attempt to recover by increasing the AoA as soon as she's unstalled, you can guess what immediately reoccurs. Application of power only exacerbates the vice unless you maintain the wing in the unstalled condition.

As for a .46 in VMAR's PC-9. At over 3kg dry weight even with a .46, this bird will it handle like an utter dog, and with its dynamic stall characteristic vice, unless you are aerodynamically erudite, situationally aware and exercise unwavering discipline in the approach envelope, as the pictures available for perusal in this thread only too amply illustrate, it won't remain in one piece for long.

Still thinking of buying VMAR's PC-9? As long as you are aware of its vices, fly it accordingly and engine it appropriately, it's fun enough to fly and it certainly looks the part in the air. Just be aware that it's unforgiving of imprecise handling in the low speed envelope or you'll pay the full price of admission if you're not ever vigilant below 'mistake recovery height' and disciplined on approach.

Yogi-Bear

Sirgun,
My VMAR PC-9 is powered by a YS .63 and flys extremely well, i don't know wether its the one i recieved or not but it flys beautifully and tracks solidly. I'll try (with a bit of altitude under me) the stall characteristics and report back after this friday. But it seems you are not at all happy with the kit or how it flys. While i wouldn't buy another it flys well and hasnt given me any scary experiences. All planes with a higher wing loading suffer from more severe stalls that's a given and flying a standard approach will not lead to any troubles. It's and intermediate plane and so will have "nastier" stalls than a trainer stalling any plane real or model on final to land almost always ends in disaster. The only way u can get out of a stall at low speeds is a big power to weight ratio to pull your self out or its a trainer and as such only needs a little correction to regain controlled flight..

Yogi-Bear

Well, It was a beautiful day for flying today and i flew 4 flights on the PC9 they went well. I tried the stall chracteristics at height and found that at idle slowing the plane to speed requiring full elevator a sharp wing drop and spin orccurred if back pressure was not realesed. I also tried spinning and found that with full up elevator and full rudder the plane spun well and when the stick where realeased took a half turn to stop, however if not allowed to pick up speed before leveling of a high speed stall would occur. Snap rolls with bower only required elevator and rudder and with aileron were very vicous. It looked so sweet with the YS pumping out heaps of smoke to stall after going vertical and start snapping in the plume of smoke. after this little test its clear that with out a basic knowledge of aerodynamics and load factors a beginner could end up in a bit of trouble quite quickly. I had a ball though and enjoyed snap rolling and spinning was an absoloute blast i haven't had that much fun in a while. On the last flight i dead sticked at 10ft at the far end of the runway and had to put it in the long grass but it came out with no damage so it was a fantastic day all in all.

Woody 51

I had a .46 sized VMAR PC-9 with a Saito .50 in it. Flew very nicely. I had to drop the tank height to make it compatible with the inverted 4 stroke. The model outlasted the motor (which dropped a valve and destroyed itself internally) so I passed the model onto a new owner. He has it flying, still, but had to re-inforce the landing gear blocks in the wings.

But for anyone wanting or looking at one of these, either VMAR or SEAGULL, 1st up, take good hard look at the new PHOENIX TUCANO.

A very similar looking model and far better quality kit. And it flies better than both the VMAR or SEAGULL offering.

sigrun

Hi Yogi-B

My post wasn't intended to rubbish the VMAR PC-9, but tell it like it is. I think I did that.

I quite enjoy flying her, but they are what they are and my caution or warning caveat stands without either amendment or apology. For the mediocre R/C pilot or those who aren't aerodynamically erudite and armed with a switched on SA, the model lifespan is limited and the end result only all too predictable. The Seagull unit is unquestionably much friendlier in its handling characteristics for the average R/C flier.

Almost without exception the Seagull PC-9's crash through either structural failure (there are a couple of items deserving of attention during construction) or pilot induced error during high speed flight. ie: Brain fart with everything's happening very quickly at full throttle.

On the other hand, almost invariably, and certainly of EVERY example I've seen of the VMAR unit, their end results from and is a consequence of what R/C fliers term 'tip stalling' somewhere on approach. Apart from interpolating the obvious from ample examples evident of their demise within this lengthy thread, I've personally witnessed 4 VMAR PC-9's go in as a consequence of this without the pilots understanding what was happening, usually with barely sufficient height to recover even if they did.

I do need to correct your comment on the following point though, if you'll pardon me in doing so? [:-]
Once a wing is deeply stalled at the outer section and rolling rapidly onto its back as is the case with VMAR's PC-9, application of full power no matter how powerful the motor (amount of excess thrust available) will simply exacerbate the situ and take the stalled model to the scene of the crash faster. The only action which will rectify the situation is to unstall the wing, and keeping it unstalled, once you have it flying again recover from the UA and adopt a positive climb attitude, ie: pointed away from the great granite rock below. Once established with the wing flying again and in the climb, the excess thrust available can actually be put to good use. A trap with the VMAR wing lies in it proneness to restalling with even minute applications elevator if after initial recovery, you don't allow it to accelerate, all of which takes precious time and space for which there is frequently insufficient latitude give proximity to the ground when it occurs on approach.

Flown appropriately so armed with an awareness of its characteristics and exercising discipline to maintain a conservative margin thus ensuring safe handling within the paameters necessary near the ground, it's unquestonably a beautiful looking model in the air, and can last an aeon. Lamentably, IME&O this requirement falls outside the performance or discipline skillset of your average R/C flier.

sigrun

Hi Woody 51

I haven't seen the Tucano in the flesh yet. Other than Farnan's advertising, probably due to available supply from the initial shipment going to favoured southern shops as is the observed modus operandi, the new Phoenix Tucano doesn't seem to have penetrated north yet.

Coming from the sister company and essentially the same factory (address) & manufacturer as Seagull, I thought the Tucano would essentially be the phenomenally successful Seagull PC-9 design just relaunched with a different cowl & canopy accompanied by a slight reshaping of the fuselage, colour scheme and appropriate decals to better resemble a Tucano relaunched with a different name.

Having aroused my curiosity, how is the wing different? Disregarding the obvious with the VMAR PC-9 and paraphrasing you, in what respect/s does it fly better than the Seagull PC-9? What have they iimproved or changed which makes the Tucano a "far bettter quality kit"?

cheers

sigrun

Yogi-Bear

Fair call sirgun
i agree you need to first unstall the wing, and then climb away excess thrust will then help you climb out at a higher angle.. i did get a little wing drop with aplication of full elevator at idle in a dive but with an understanding or aerodynamics i know to reduce back pressure and ease it out... i can see though how a novice could find it hard to understand and correct. All in all though i do like the challenge and the snaps are so much fun as are the spins i just love flying anything
Will
BTW are you a pilot, engineer or a just and enthusiast? My knowledge is coming from CPL and ATPL training that im undertaking.

sigrun

Hi Yogi-B

My remark wasn't in any way intended as veiled one-upsmanship, just clarifying an aerodynamic fact dictated by the irrefutable laws of physics. That you appreciate and enjoy your PC-9 is pleasing to hear. It looks very attractive in the Swiss colour scheme. You'll have to post some images with the cowl on? It's probably due to your awareness of aerodynamics that yours has survived this long. I too enjoy flying VMAR's PC-9 due to the requirement to fly it accurately and with discipline within the approach envelope. In answer to your question, enthusiast since childhood and pilot for over 32 years, professional for 27 of them. ATP (US) ATPL (AU) et al.

cheers

sigrun

RLefebvre

My Feedback: (1)

I still contend that it flies just fine with a TT 46 Pro. It had plenty of power for sport flying. It couldn't hover, or unlimited vertical, but it pulled it around fine with a good climb rate, etc. That engine is now in a TT Decathlon, a much heavier airplane, and it's fully aerobatic. Plenty of power for round loops, great hammerheads, etc.

Mine crashed because I flew it into the ground. It didn't stall, snap or spin. Maybe it shouldn't be a first low-wing for the average pilot, but I wouldn't call it "flawed". It was easier to fly than my Decathlon which will snap just by giving full high-rate elevator, even at high speed.

Maybe the people who are having it snap, are because they are using high rates. I was flying mine on low rates. I don't care what anybody on the internet tries to tell me. I saw it fly with full up elevator at 1/4 throttle. It just plowed through the sky with a nose high attitude. The best pilot in our club took it up and said it had no problems at all.

Yogi-Bear

Hey sirgun,
enthusiast since childhood, ppl(A), CPL(A) theory, 100hours in 172's studying atpl (A) theory, I've got a bit to catch up on hehehehe. Amazing who you talk to and to flying the pc-9 i always enjoy a challenge after all whats life without challenges?
Will

jcilia

Guys, just to let you know that I have had 3 totals ( twice wing sets and once fuse.) due to tip stall and then spin. Last total I was practicaly not touching the controls. I flew with an MDS 48 which is hopeless and under powered, ASP 61 FS fine but still could do with a bit more power and Irvine 53 2s which was just fine. Whatever anyone says I will not touch VMAR with a barge pole.

Joe

PS last total I have rebuilt the fuse from scracth, however does not look like a PC 9 anymore

bobbykokinos

Sorry to bring up an old thread. But, has anyone side mounted the engine? I had a TT .46 is my old PC9 and I had nothing but problems with it. I got a new PC9 and am considering side mounting the engine but dont know how I would do it with the front gear being in the way of the muffler.

If anyone has any suggestions, they would be appreciate. Pictures also would help!

Thanks

jcilia

Easy just mount at 11.00 or 10.00 O'clock and don't bother about the cowl, In fact I have just put it all back together and have installed an Irvine 53. Will give it a test flight this weekend.

bobbykokinos

You mean just leave the cowl off totally?

jcilia

Yes - that's what I have done - after all it has never survived that long to worry about the cowl, also at least I still have the cowl in one piece I do agree that it looks cool with the cowl on but after all it's the flying which is important at least for me.

BTW is your's a Seagull as mine is Vmar......

Wully

My Feedback: (26)

Amen on problems with the inverted engine with the PC-9. I'm having the same problems. I tried lowering the tank as far as I can,,,,and I still have flooding problems. I tried looping the carb line per suggestions...etc.etc.

I removed my engine last weekend trying to sidemount at a 90° angle like you, per suggestions from other flyers, but the fuselage gets in the way, then I turned it a little more like 110° then the wing got in the way of the muffler, so you have to turn it about 150-160° to get the muffler above the wing, so I'm not sure what I'm going to do at this point myself.
I love the way the plane flys and looks, but i can't handle this flooding crap every weekend.
Frank

sigrun

IME the default engine mounting will still allow flooding even with the tank support dowel removed and tank height lowered as far as it can be without removing the tank floor pan and exicising the supporting formers. Option A.

Rotating the engine to 270 degrees does significantly alter the carb/tank height relationship, but as you've discovered presenting another problem with most standard 2 stroke mufflers, except perhaps for ST owners. Offsetting instead to 250 or 260 degrees may avoid muffler contact with the nosewheel leg, but unfortunately, because the design is a trike, any rotation of the engine mount means drilling the mount ring or replacing the mount to accomodate that nosewheel leg. Another PITA.

Haven't tried it myself, but perhaps locating it at 225 degrees may be of benefit, although it will mean excavating the guts out of the cowl to accomodate it, perhaps not altogether a bad thing? IME whilst that cowl inarguably looks great in the air when fitted, it's been designed without forethought of flow routing, in particular circulation and egress with the result that the engine does notably run a lot hotter when it's fitted despite the open centre section. If you're running 10% or > nitro and turning a 10" prop, this does mean that either extra oil consisting of some castor or a richer tune is required, especially with the encumberance of the small and tall tank vs carby height relationship causing a an increasingly leaner run throughout the flight, quite significant by the time the tank is ½ empty or <. Although altering the engine fitting to 225 degrees doesn't raise the carby by much, it will OTOH prevent the residual oil and fresh fuel from gravity pooling in the top of the combustion chamber, and notably within the glow plug itself, so there is advantage to be gained.

For my own, on my next Seagull PC-9 fit-out, I will adopt a multi-pronged approach. It's such a good model, the effort is justified as worthwhile. I will obtain a larger, longer and lower proifile tank such that the change in volume isn't represented by so large a displacement of mean fuel head height. I will take the time to open up the bottom of the fuel tank compartment, excise and reinforce as necessary until I achieve an acceptable carb vs tank height relationship. I will replace the supplied clamp cast mount with a modified Dave Brown resin unit and will offset the engine to 225 degrees or thereabouts to achieve a marginal increase in carb height. But most saliently, this will prevent gravity pooling of residual oil or freshly introduced fuel directly onto the plug element or in the plug recess. Lastly, I will open up the cowl to accomodate this and facilitate better cooling I will try dremelling a couple of shaped egress holes in the upper sections of the cowl, and form internal NACA shaped ducts with some glass and epoxy resin to promote flow circulation around the engine case.

I know it seems like a nuisance and a lot of work, but I love the way this model flies so much IMO it's worth it to remedy the issues mentioned. Compared to building a model from scratch as we used to have to, the modifications required are insignificant.

jcilia

Guys, as intimated I will not bother with the cowl this model does not survive long enough, however one question I would like to ask the VMAR owners. how much weight did you add to the front to get a proper CG. mine needs 60g with an Irvine 53.

Wully

My Feedback: (26)

Your suggestion about the longer lower profile tank is a winner in the Seagull PC-9. Bought a Sullivan 12oz tank yesterday and it made all the difference. Yes, it does extend into the aft section, but it doesn't interfere with the wing at all.
I also switched to a plug w/ an idle bar which I think helped as well.
I'm running a OS 46 FX w/ a tuned pipe, 11x6 APC prop and she is screaming. I might drop down to an 11x5 just to hear the tuned pipe do it's thing.

sigrun

Pleased to hear it made some difference to your problem. The supplied tank is totally wrong for this model, exacerbated by the default engine to fuel tank mounting relationship. PS: Weather in the pic looks magic. Love those kinds of days. [:-]

jcilia

Guys, VMAR PC9 flew last Saturday just one flight as I have problems with the front wheel keeps getting loose on landing. Anyway not bad after so many repairs but it is terribly unstable and will snap the min. I reduce throttle to say 1/8 It goes like a bomb with the Irvine 53, flying at 3/4 throttle is more then enough. will give it another shot this weekend if the wind is right btw it was force 4 gusting 5 last Saturday but it was not much of an issue with the PC 9

negeilum

I have just received a Seagull PC( for a birthday gift. I have read most of the posts in this thread and it seems like I received the better choice for the average pilot. I didn't see this post until after completing everything but the tail section. The construction of mine lokks a little different inside than the pics I have seen posted. Is it really necessary to reenforce the firewall? The I am running an OS 46fx and everythin was done according to the instructions. Can I assume based on all of the posts regarding flooding that I will definitely have this problem? Should I disassemble and start over? From a flying characteristic standpoint, the engine came from Twinstar modified for single engine. I was wondering if these two planes fly similar as they both have a symetrical airfoil. Any info would be greatly appreciated.

Desertlakesflying

My Feedback: (28)

From what I can see the firewall on the PC-9 is fine. It looks identical to the Phoenix Models Strega firewall connection. No problems with it at all. Well except my brothers 125MPH nose dive from about 3 feet off the ground inverted. Then the firewall broke. Then again I dont think any firewall would make it through that one. Most of the plane survived pretty well but not enough to rebuild. Wing could be used again on another one. 9 pounds of epoxy isn't always better than a good glue joint. I might consider making the wing dowels a little bigger also.
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Desert Lake "Flying Club"
Proud members of the "AMA"
Aeronautic Maniacs Association
"Flying Club" up here in Northern Nevada that is just a term for a buch of old guys with nothing better to do than make up rules and fly YOUR plane for you. I like our "Club". Miles of runway in a dry lake, and many competent pilots who will actually train you, not just fly YOUR plane for you. It's safer than the AMA sanctioned fields here.

Desertlakesflying

My Feedback: (28)

Just built the Seagull PC-9 in about 4 hours on Saturday and Flew it on Sunday. Thing flies as good as it looks. I have all the end points set at half until I get used to it and it is already responsive. I'm happy with the Seagull. Was landing a little fast so I just mixed in flapperons. Lands nice now. Won't tip stall or anything I can almost creep it in at full flaps. I'm flying a Magnum 52, and a 10X7 prop. Plane is a rocket. Camera man could only get blurry pics of it...lol Oh and as stated above....firewall is fine. I was guessin from pictures I had seen now in person it is fine. I would reccomend it as a second plane. After all it is my second plane
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