Handling Issues

All problems and technical questions concerning our Cessna O-1/L-19 Bird Dog are discussed here.
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cyberpilot
Posts: 7
Joined: 12 Mar 2009, 23:10

Handling Issues

Post by cyberpilot » 28 Dec 2009, 07:57

Is anyone else having problems taking-off and landing the Bird Dog?
I'm an experienced flight simmer as well as a RW recreational pilot but I just can't get the hang of this aircraft and, yes,I've read the manual.
Half the time the aircraft will veer to the left on take-off, even though I am correcting for torque, and then lurch to the right before doing a ground loop.
Landings are also a hit and miss affair with the aircraft performing similar gyrations upon touching down.
I've also had issues doing gentle stalls which in no time at all develop into a violent wing drop and almost uncontrollable spin.
Then there's the problem of the spinning gyro which no amount of clicking on the knob stops as well as the nav tuning knobs which don't work.
I would have thought much of this would have been sorted out in the beta testing.
Have to say I'm really disappointed in what is otherwise an excellent product.


Frank

sbflyer
Posts: 5
Joined: 25 Dec 2009, 23:48

Re: Handling Issues

Post by sbflyer » 28 Dec 2009, 09:53

I'm only a simulator pilot, but have noticed a tendency to weathervane like all
taildraggers in a 5 knot or more crosswind. The phenomenon is more pronounced than
the default Maule or RealAir Scout for example, but not as bad as in the default Cub.
This is with a no-flap takeoff.

With 15 or 30 deg. flaps, the BirdDog does seem really sensitive to crosswind on takeoff,
more so than on landing. I'm interested in what realworld taildragger pilots have to say.
i7 920 @3.8 6 GB Corsair Dominator 480 GTX WIndows 7 64 bit Prof. ASRock Extreme X58

teeboy
Posts: 13
Joined: 26 Dec 2009, 22:17

Re: Handling Issues

Post by teeboy » 28 Dec 2009, 21:03

I guess it can't be just me then! Definitely seems twitchy with any wind, but I haven't suffered any ground looping apart from a mild attack on my second landing. Still managed to keep it pointing roughly down the runway tho'. It does seem to have a peculiar crab with any crosswind which rudder doesn't seem to affect.

Gyro cages by rolling the mouse wheel - its a pity that most of the other knobs/ switches don't respond the same way...

Nick

LPC
Posts: 8
Joined: 27 Dec 2009, 21:25

Re: Handling Issues

Post by LPC » 29 Dec 2009, 00:30

I also wondered about the spinning gyro to start with but it can be caged with the click of the mouse wheel. I don't know why that isn't mentioned in the manual anywhere.

I tend to agree about the handling though - with any wind at all it becomes practically unflyable.

cyberpilot
Posts: 7
Joined: 12 Mar 2009, 23:10

Re: Handling Issues

Post by cyberpilot » 29 Dec 2009, 00:38

I used to fly a Piper Cub in the real world and it was never as tricky as the BirdDog.
In FSX the BirdDog is flyable in calm conditions but any sort of cross wind and it becomes a major handul on take-off and landing to the point where it can sometimes become uncontrollable.
IMHO there is something wrong with the flight modelling that needs fixing.
Today I've also encountered another issue ... FSX crashed midway through a flight ... still trying to figure out why.

Frank

sdflyer
Posts: 14
Joined: 29 Dec 2009, 01:09

Re: Handling Issues

Post by sdflyer » 29 Dec 2009, 01:28

cyberpilot wrote:I used to fly a Piper Cub in the real world and it was never as tricky as the BirdDog.
In FSX the BirdDog is flyable in calm conditions but any sort of cross wind and it becomes a major handul on take-off and landing to the point where it can sometimes become uncontrollable.
IMHO there is something wrong with the flight modelling that needs fixing.
Today I've also encountered another issue ... FSX crashed midway through a flight ... still trying to figure out why.

Frank
I haven't tried Bird Dog in FSX yet and have never flown Cub. But I would imagine a big difference in handling both airplanes due to more powerful engine of Bird Dog

Cessna
Posts: 3
Joined: 28 Dec 2009, 12:24

Re: Handling Issues

Post by Cessna » 29 Dec 2009, 03:38

I was having trouble with touching the tailwheel first causing me to groundloop when landing. The perspective in the Bird Dog gives me the illusion that I am pitching nose down when in level flight causing me to overcompensate when flaring. I do agree though the Bird Dog has some handling tweaks to be made.

sdflyer
Posts: 14
Joined: 29 Dec 2009, 01:09

Re: Handling Issues

Post by sdflyer » 29 Dec 2009, 09:59

OK, I finally get my hands on flying Bird Dog.
Well, now I see a lot of problems. Elevator authority in Bird Dog seems like way off. Airplanes suffers from static lateral and directional stabilities . I'm not sure it was a case. I tried to do couple power off 180 and found myself ground looping, which seems like a nonsense considering that engine was on idle or turned off. The bank angle aver 30 degrees is very unrealistic taking into account wing dihedral, perhaps it should be tuned up a bit. You definitely have to do a lot of work.

Hank
Posts: 4
Joined: 25 Dec 2009, 13:20

Re: Handling Issues

Post by Hank » 29 Dec 2009, 22:10

Gents, this bird handles perfectly!
Some tips to increase your pleasure:

One reminder for all....let the BD liftoff by herself, don't push the stick forward. If you do, you actually force to let directional control done by rudder alone (you lifted the tail wheel....the OTHER directional control but for lower speeds) but isn't affective yet. (That's why she'll veer to the left.....)

Simply put....line up and power up, and don't do anything else. Eventually you'll notice a nose drop...once dropped your rudder is fully effective (enough speed) and you can take controls and enjoy her beatiful handling.

Also, when using flaps, take care of your own speed as well that of the wind. You'll never land with a full flaps configuration with a heavy crosswind with such a light plane.

Also, when you notice a tendency to roll either left or right....make sure you DRAIN both fuel tanks equally. This has to be done manually by switching between Main and Aux tanks. (I still wonder though why the didn't name them simply Right and Left....). Anyone will know the difference in balance if one wing tank is full and the other one empty.

I don't want to sound like some smartass, all I want to do is to help you guys.
Cheers

LPC
Posts: 8
Joined: 27 Dec 2009, 21:25

Re: Handling Issues

Post by LPC » 29 Dec 2009, 22:48

Hank wrote:Gents, this bird handles perfectly!
Some tips to increase your pleasure:

One reminder for all....let the BD liftoff by herself, don't push the stick forward. If you do, you actually force to let directional control done by rudder alone (you lifted the tail wheel....the OTHER directional control but for lower speeds) but isn't affective yet. (That's why she'll veer to the left.....)

Simply put....line up and power up, and don't do anything else. Eventually you'll notice a nose drop...once dropped your rudder is fully effective (enough speed) and you can take controls and enjoy her beatiful handling.

Also, when using flaps, take care of your own speed as well that of the wind. You'll never land with a full flaps configuration with a heavy crosswind with such a light plane.

Also, when you notice a tendency to roll either left or right....make sure you DRAIN both fuel tanks equally. This has to be done manually by switching between Main and Aux tanks. (I still wonder though why the didn't name them simply Right and Left....). Anyone will know the difference in balance if one wing tank is full and the other one empty.

I don't want to sound like some smartass, all I want to do is to help you guys.
Cheers

You don't sound like a smartass and I appreciate the help but, have you flown her at all with 'real' weather? Any wind over about 10 knots? The handling is completely unrealistic. In calm default weather it's just about ok but try using ActiveSky with anything other than a gentle breeze and she is impossible to control correctly.

sdflyer
Posts: 14
Joined: 29 Dec 2009, 01:09

Re: Handling Issues

Post by sdflyer » 29 Dec 2009, 23:02

Hank wrote:Gents, this bird handles perfectly!
Some tips to increase your pleasure:

One reminder for all....let the BD liftoff by herself, don't push the stick forward. If you do, you actually force to let directional control done by rudder alone (you lifted the tail wheel....the OTHER directional control but for lower speeds) but isn't affective yet. (That's why she'll veer to the left.....)

Cheers
Hank like you said L-19 is light airplane, so there should be sufficient slip stream generated by the prop to have sufficient rudder authority. One of the short field take off technique used for light taildraggers consist of holding the brakes while applying full power, then gently pulling stick forward, rise the tail, and release the brakes for take off roll.

For some airplane with more powerful engine it's indeed recommended to pull stick up and hold tail down until airplane lifts off . It's mainly done due to excessive P-factor, torque, sliptream and gyroscopic precession and low rudder authority due prop effects generated by powerful engine.
In case of L-19 with O-417 rated as 213 hp I don't think it would be a case. At least when I flew SNJ-4 I took off conventional "tail up" way just like it's been taught in Citabria, Decathlon or Cub

Hank
Posts: 4
Joined: 25 Dec 2009, 13:20

Re: Handling Issues

Post by Hank » 30 Dec 2009, 01:29

sdflyer wrote: Hank like you said L-19 is light airplane, so there should be sufficient slip stream generated by the prop to have sufficient rudder authority. One of the short field take off technique used for light taildraggers consist of holding the brakes while applying full power, then gently pulling stick forward, rise the tail, and release the brakes for take off roll.

For some airplane with more powerful engine it's indeed recommended to pull stick up and hold tail down until airplane lifts off . It's mainly done due to excessive P-factor, torque, sliptream and gyroscopic precession and low rudder authority due prop effects generated by powerful engine.
In case of L-19 with O-417 rated as 213 hp I don't think it would be a case. At least when I flew SNJ-4 I took off conventional "tail up" way just like it's been taught in Citabria, Decathlon or Cub
....true, rudder authority could, or better should be better modeled/written. The required speed, as of now, is a bit to high, and yes I'm aware of that. But looking within the FSX perspective, and own experience, rewriting the airfile is like opening a can of worms. So with that in mind I just made these advices as it is the safest way to take off with the BD without a chance to veer to the left.....and really enjoying this wonderful aircraft.
LPC wrote: You don't sound like a smartass and I appreciate the help but, have you flown her at all with 'real' weather? Any wind over about 10 knots? The handling is completely unrealistic. In calm default weather it's just about ok but try using ActiveSky with anything other than a gentle breeze and she is impossible to control correctly.
...I use the wx engine of FSX myself, and fly the BD in northern Canada with winds up to 30 kts with no problems at all. Sure, gusts are there, but I get similiar behavior like the A2A J3 and most light planes from Carenado.
I even manage to trim the plane with crosswind and arrived where I should be, without touching my controls. That's what I call stabilitly. 8)
Not to brag about it, but I'm a desktop pilot since FS5.1, and always try to get things simulated as real as possible.

Cheers,
Hank

sdflyer
Posts: 14
Joined: 29 Dec 2009, 01:09

Re: Handling Issues

Post by sdflyer » 30 Dec 2009, 02:00

Hank wrote:
....true, rudder authority could, or better should be better modeled/written. The required speed, as of now, is a bit to high, and yes I'm aware of that. But looking within the FSX perspective, and own experience, rewriting the airfile is like opening a can of worms. So with that in mind I just made these advices as it is the safest way to take off with the BD without a chance to veer to the left.....and really enjoying this wonderful aircraft.
Hank

Well lets hope developers will tune it up. Other than that pretty good looking plane :)

LPC
Posts: 8
Joined: 27 Dec 2009, 21:25

Re: Handling Issues

Post by LPC » 30 Dec 2009, 02:36

Hank wrote:
sdflyer wrote:
LPC wrote: You don't sound like a smartass and I appreciate the help but, have you flown her at all with 'real' weather? Any wind over about 10 knots? The handling is completely unrealistic. In calm default weather it's just about ok but try using ActiveSky with anything other than a gentle breeze and she is impossible to control correctly.
...I use the wx engine of FSX myself, and fly the BD in northern Canada with winds up to 30 kts with no problems at all. Sure, gusts are there, but I get similiar behavior like the A2A J3 and most light planes from Carenado.
I even manage to trim the plane with crosswind and arrived where I should be, without touching my controls. That's what I call stabilitly. 8)
Not to brag about it, but I'm a desktop pilot since FS5.1, and always try to get things simulated as real as possible.

Cheers,
Hank
Maybe it's just ActiveSky Advanced? I flew around Alaska in FSX realworld weather earlier and it wasn't too bad but when I flew a little later with ActiveSky it was like flying a paper airplane! When I switched to the A2A Cub I was quickly able to get control again. There is something strange going on somewhere :?

jetjerry
Posts: 5
Joined: 01 Jan 2010, 02:04

Re: Handling Issues

Post by jetjerry » 01 Jan 2010, 04:29

Hello guys. My name is Jerry A.

I used to fly a Bird Dog many years ago in the US Army.
Actually it seems to handle very much like a real BD I think...keeping in mind it has been many years now.
The BD is over powered with 213hp, but more importantly, it is nose heavy with that old O-470 in it...especially when flying solo.
It does have a tentancy to ground loop and is the only tail dragger I ever flew where you really should keep your heels up off the floor and be very ready to hit those brakes! The rudder was small for the P-factor and torgue.
When you take off in the BD you keep the tail wheel on the ground, you do not push the nose over and roll on the mains. When you start to feel the nose drop you actually pull the stick back to hold the tail on the ground and let the dog fly itself off...else it may bite you.
In this regard I think the flight dynamics are done pretty well.
The only comment I can make about handling is: I think it used to break ground more quickly in the real one. Again, I'm not sure I remember this right, but it seems to me we could get it off the ground in under 400 feet....no wind.

My comments may not help anyone here. I just wanted to say that it is nice to find an old friend again...even if only in cyber space.

Thank you for the BD!

Jerry A.

SGTMAJOR
Posts: 86
Joined: 03 Sep 2006, 04:17
Location: California, USA

Re: Handling Issues

Post by SGTMAJOR » 01 Jan 2010, 21:25

jetjerry wrote: I used to fly a Bird Dog many years ago in the US Army. Actually it seems to handle very much like a real BD I think...keeping in mind it has been many years now.
Jerry - Great to have someone who has actually flown this bird in real life, provide some input. However, I do have a few "concerns" myself on the aircraft. Like you, it has been many years since I've gotten behind the stick...... and have never flown a BD...., but there are a few instances where something seems a little off.

I'm pretty much okay with the overall handling of the aircraft while cruising and in normal flight. Where I start having concerns is on the approach and landing. Again....keep in mind most of my real world flying was in Cessna 150's, & 152's, also light aircraft and not nearly as powerful as the bird dog. In the 150&152...... I'd start setting up the approach for the pattern around 4-5 miles out......slowing to pattern speed..... carb heat..... flaps one notch.... and still would have to watch my airspeed closely as I had a tendancy to come in hot by picking up a little speed on the decent.

The Bird dog however, I can zoom in with a 1000 ftm decent......no flaps..... no carb heat and picking up speed to around 130kts....... about a half-mile to mile out on short final, chop the throttle.... still holding the decent and it will easily slow to 80kts or so over the threshold. That seems extremely strange to me..... never have piloted or flown in a light aircraft and experienced that type of behavior of actually slowing in a decent like that.

I also noticed on power on and power off stalls. The power on stalls handled EXACTLY how I would expect a Cessna of this weight/size/power to handle...... seeemed very realistic to me....... actually breaks about like a 150&152.....I expected a more violent break considering the larger engine..... but having not actually flown one there is no way to know.

The power off stall however, I'm not so sure. The stall itself seems fine...... but it seems if I let the stall develop into a spin...... I've gotten some strange flopping and has even developed into a flat spin several times which is completely unrecoverable from 3500 feet. (power on/off....stick input of any kind is totally useless etc.) Again.... I haven't flown a bird dog in real life...... but I also haven't ever heard of a light Cessna going into a flat spin of this sort.

Please don't misunderstand me...... This is a BEAUTIFUL aircraft and very nicely done and I would never attempt to criticize the hard work the team has put into this wonderful model..... but just question if there are some issues being picked up with the various computer setups that simmers have that may need some addressing. It's like having a beautiful Isaak Levitan painting in perhaps a not so lovely frame. (smile)

Cheers,
Steve R.
SgtMajor, USMC, (Retired)

jetjerry
Posts: 5
Joined: 01 Jan 2010, 02:04

Re: Handling Issues

Post by jetjerry » 02 Jan 2010, 00:17

SgtMajor Steve...a great pleasure to have a SgtMajor in this forum.

I was a CWO in VN where I flew the Army CV2B, Caribou in 1966. The last Army pilots to fly it. My replacement were AF units that took over operational use of the Bou. A good airplane!
I ended up in Germany flying the single engine Otter (DHC-3). Since the Army went the way of helicopters and lost most of it's fixed wing, I got out and flew elsewhere.

I think overall SW did a good job with their Birddog. I am having loads of fun with it!

All the BDs I flew were Army and thus had fixed climb props (low pitch) on them for tactical use. They would jump off the ground quickly and climb rapidly, but did not cruise at a fast pace for 213hp. I'd say about 100 kts is correct. This also allows for greater speed bleed off when reducing power. The Army taught power approaches...attitude and airpseed over the obstical and carry the power to the flare point then idle with full flaps and immediate brakes. It would land in about 200 feet if you had it all nailed. The civil model is not certified for flaps 60...only 45.

I tried to do stalls and spins with this model. It doesn't seem to be very realistic to me...as best I can remember. In a spin, which the Army taught in Basic flight training, it would roll over the top when you kick rudder. Great fun when I was young and stupid. The nose was so heavy that it would rap up those turns quickly. We were limited to 4 turns.

1. I can not get any of the CUSTOM CONTROLS to work. Ctrl+Shift+?...none work for me. Only the FSX wing fold works...cowling open.
2. I get a loop sound with the TO(F) model when everything is shutdown. It sounds like the engine is still running...or APU etc.
3. There are no QNH numbers in the Kollsmen window on any of the altimeters.
4. The tail wheel should brake lose from it's turn limit cam when you apply brake and then turn sharply...this model does not.
5. The TO (F) model has a constant speed prop and should develope higher rpm than it does...in all flight attitudes...using the prop control to adjust it's rpm rather than airspeed.
6. There is something funky about the nav's. I haven't figured it out yet. The numbers don't agree and sometimes the ADF justs stops pointing to the staion.

I don't mean to sound critical here. Just some things I'd like to see fixed.

Overall I'm having a blast pretending I'm young again. Remember...you never do a wheel landing in a BD...it's not a Stinson L-5...which would make a great next project!

Take care Steve...thanks for your service!

Jerry A.

SGTMAJOR
Posts: 86
Joined: 03 Sep 2006, 04:17
Location: California, USA

Re: Handling Issues

Post by SGTMAJOR » 02 Jan 2010, 11:33

jetjerry wrote:I think overall SW did a good job with their Birddog. I am having loads of fun with it!
CWO Jerry.....Always nice to have a fellow service man to talk shop with. (smile) I didn't enlist in the Corps until 72.... entering active service in June of 73. Loved every minute of it!!! Started on the ground side but switched to aviation on the second hitch. (Avionics.... UH-1N, AH-1J, AH-1W, VH-1N, VH-3D and two tours of Instructor Duty) Always wanted to retire as a SgtMajor so went the 1stSgt, SgtMajor route back on the ground side the last 7+ years. Good duty, good friends and got to see a lot of this old world. Really miss the ship board time of all things......Smile.

On the Bird Dog...... I concur whole heartily.... I think SW did a very nice job with the aircraft overall and I truly appreciate the hard work, however, I find the same issues you do, with the exception of the custom controls..... mine seem to work fine overall, however, the "Shift-0" to remove the ord. does not.....OR.... I just haven't figured it out yet. (Hate to ask a silly question..... but you ARE using the Custom Controls from the VC, correct? Only from the VC will they work.)

Ahhhh...... fixed climb prop.... hadn't thought of that..... that would most certainly make a difference. Although I had another flight this evening and I turned base with a 1000-1100 fpm descent, 130kts and chopped power on turning final at 500' AGL, no flaps, no carb heat, and touched down lightly at 75kts making the first turn off the runway. Maybe that is correct..... but seems a little too much drag or something. (Maybe just great piloting skills...... Grin)

But with the minor issues, I'm still having a great time flying the bird and it's still a very good looking (if not one of the best) rendered aircraft in FSX.

Best wishes,
Steve R.
SgtMajor, USMC, (Retired)

jetjerry
Posts: 5
Joined: 01 Jan 2010, 02:04

Re: Handling Issues

Post by jetjerry » 04 Jan 2010, 00:33

Steve:

Take the Dog up and stall it with full flaps and about 1700rpm...like you were on a stol app.
You should find it stall out at about 50-55 kts. Not sure about this anymore.
I think you may be flying the app and landing too fast.

When you get a good feel for the stall speed, just fly the app at about 1.1...not the normal 1.3 and chop the power as you flare. It should payoff immediately and roll only a 100-200 feet if light wind.

I did get the "custom controls" to work...using the RT Ctrl & Shift keys. The left ones don't work for me.

Still having fun with it.

Take care,

Jerry

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