Queries about flying.

[Instinctloh]

Folks,

I ve a few questions which need your guidance.

My cessna crashed before and today I realised that when at 1/3 throttle or zero throttle, the plane can fly straight. However once I push to half and above, the plane start to climb (great angle).

I dun recall I have this issue before thus Suspecting is it possible due to the stick mount is bent? If is really the case, anyway to rectify?

I used to fly with 1300 batt now switch to 1800 cos need the wt of the batt to level (cg).

If I switch back to 1300, i need to put approx 30g of wt in front. Is this not advisable for heavy wt?

The plane was design for 800 - 1000 batt why even if I use 1300 still can't get the right cg?

Is it due to the manufacturer fault? I'm just trying to know more about cg not to blame anyone.

Thks in adv

[shoyn]

There are a few possibilities:

1. Your battery went towards the back of your plane
2. Since you are using a higher MAH batt, there will be slighly more power supplied to your motor. (going by the formula P=IV) Thus it is going vertical
3. There is alot of upthrust when you mounted your motor onto your plane.

That's all I can think of.

[nic]

Some planes are designed for brushed motor and nicad batts. When we plug in brushless and lipo, we either have to add weight or mod it. Otherwise it will be sensitive to CG and overpowered. If it is gws, there are lots of old tips on line in other forum to mod the planes for brushless/lipo setup. Just have to google for them.

[sherchoo]

There are a few possibilities:

1. Your battery went towards the back of your plane
2. Since you are using a higher MAH batt, there will be slighly more power supplied to your motor. (going by the formula P=IV) Thus it is going vertical
3. There is alot of upthrust when you mounted your motor onto your plane.

That's all I can think of.

Slight correction.

Higher mAH does not give you more power. it just gives you longer discharge time.

Even using P=IV

Current does not change as the load/motor is the same, voltage definitelly does not change so Power will remain the same.

[dloh]

diff batteries

Folks,

I ve a few questions which need your guidance.

My cessna crashed before and today I realised that when at 1/3 throttle or zero throttle, the plane can fly straight. However once I push to half and above, the plane start to climb (great angle).

I dun recall I have this issue before thus Suspecting is it possible due to the stick mount is bent? If is really the case, anyway to rectify?

I used to fly with 1300 batt now switch to 1800 cos need the wt of the batt to level (cg).

If I switch back to 1300, i need to put approx 30g of wt in front. Is this not advisable for heavy wt?

The plane was design for 800 - 1000 batt why even if I use 1300 still can't get the right cg?

Is it due to the manufacturer fault? I'm just trying to know more about cg not to blame anyone.

Thks in adv

Suggestion,...have u try changing to a bigger(and thus heavier) motor? That might solve ur cg issue,..normally adding dead weight is the last option, see if u can change the position of Rx, ESC or maybe use a bigger ESC...if u have room

[Instinctloh]

Suggestion,...have u try changing to a bigger(and thus heavier) motor? That might solve ur cg issue,..normally adding dead weight is the last option, see if u can change the position of Rx, ESC or maybe use a bigger ESC...if u have room

Nope never thought of changing motor.

The fact is that if is only a few grams I dun mind adding but now is approximately 30 grams(if I'm using 1300 batt). Tats why I decided to use a 1800 batt to achieve that.

[Instinctloh]

There are a few possibilities:

1. Your battery went towards the back of your plane
2. Since you are using a higher MAH batt, there will be slighly more power supplied to your motor. (going by the formula P=IV) Thus it is going vertical
3. There is alot of upthrust when you mounted your motor onto your plane.

That's all I can think of.

Eeerrrrrrr actually bro is kinda a bit chim for me cos dun really know about that.

Ok beside that, really no possibility that the motor mount is bent?

Or rather let me rephrase it. If my stick mount is not straight (not parallel to the ground) will that cause the plane to fly upward or downward?

[jerry97]

.

hi Instinctloh there are quite a few models of cessnas which one are u referring to?

[Crafter]

Has down-thrust angle changed?

Folks,
My cessna crashed before and today I realised that when at 1/3 throttle or zero throttle, the plane can fly straight. However once I push to half and above, the plane start to climb (great angle).

I dun recall I have this issue before thus Suspecting is it possible due to the stick mount is bent? If is really the case, anyway to rectify?

Hi dloh,

You're saying that your plane sustained some damage in a crash, and now (after repairs?) handles differently? Perhaps a picture or two of the damage areas may help others here offer you appropriate advice. Certainly, a shot of your motor mount may be what's needed, as you have mentioned about the 'bent stick mount'.

Your description of 'climbs by itself under higher power input' would lead me to suspect that your motor down-thrust angle has changed, probably upwards? In case you're not aware, motor down-thrust is basically mounting your motor pointing downwards (when the plane is upright and level with the gorund), usually about 2 degrees or so, variable. Pointing the motor slightly towards the ground helps counteract the increased lift generated when you power up (plane flies faster, more lift generated, plane tends to climb by itself). This is assuming the CG position of the plane hasn't shifted backwards with all the 'change of battery' that you also mentioned.

If there are experienced flyers where you fly, perhaps approach them to check out your plane for you. Hope this helps.

[shoyn]

Slight correction.

Higher mAH does not give you more power. it just gives you longer discharge time.

Even using P=IV

Current does not change as the load/motor is the same, voltage definitelly does not change so Power will remain the same.

As a matter of fact, it does. Have done some experiments. When I used a 2200mah 20c 3 cell batt and a 3000mah 20c 3 cell batt on the same plane, there is slightly more thrust when i used the 3000mag 20c 3 cell batt. The increase in power is not that significant, but it does give a little umph to the motor.

[Instinctloh]

hi Instinctloh there are quite a few models of cessnas which one are u referring to?

Not too sure which model.

Is a high wing cessna that need rubber band to secure wing to body.

There is numbers (decal) says 747 (if I din recall wrongly)

[Instinctloh]

Hi dloh,

You're saying that your plane sustained some damage in a crash, and now (after repairs?) handles differently? Perhaps a picture or two of the damage areas may help others here offer you appropriate advice. Certainly, a shot of your motor mount may be what's needed, as you have mentioned about the 'bent stick mount'.

Your description of 'climbs by itself under higher power input' would lead me to suspect that your motor down-thrust angle has changed, probably upwards? In case you're not aware, motor down-thrust is basically mounting your motor pointing downwards (when the plane is upright and level with the gorund), usually about 2 degrees or so, variable. Pointing the motor slightly towards the ground helps counteract the increased lift generated when you power up (plane flies faster, more lift generated, plane tends to climb by itself). This is assuming the CG position of the plane hasn't shifted backwards with all the 'change of battery' that you also mentioned.

If there are experienced flyers where you fly, perhaps approach them to check out your plane for you. Hope this helps.

Actually the damage is really v minimal in fact the only visible damage is my props n cowl.

Is during my landing. As it touches down the plane swerve to the right and I am not able to counter on time thus heads on to the kerb.

My prop broke and the cowl crack.

When I inspect the motor, there are slight vibration when I throttle. The shaft is also slightly bent. Realized when I trying to tighten the nut with a new prop. I try to straighten it but still bent a little.

Plane still able to fly with no difficulties but that's the only issue that I faced.

Will try to switch back to 1300 and see if the climbing issue persist during my next flight.

[Instinctloh]

Just to add on,

The batt did not moved at all as I mod the compartment in a way that the batt is being pushed to the front with no room for movement.

[Instinctloh]

More queries

Folks,

I have more queries about flying.

I started with my sim and really make a point to fly everyday for an hour without fail continuously for 2 mths.

I can land and fly flawlessly in the sim without crash unless I'm not serious and try to play stunts in it.

My queries are :

1) I have been trying to land as smoothly as possible but I just can't keep the plane in line with the landing strip. Worst, is so hard to gauge the distance from the ground and is either overshot or a super rough landing and just pray hard that no damage to the plane.

Mind you Im practicing with my cessna. Is the easiest of all as it can off throttle n it will glide. Imagine if I can't even land such a simple plane how to handle others that dun glide when off throttle. Is really maddening.

2) I have been practicing figure 8 for the past few days as my friend point out to me that I tend to fly anti clockwise n super weak in clockwise direction. Is there anyway to achieve it better?

3) I have bought the funjet as was told that is quite easy to fly as it b v fast and at the sometime can be v slow. Same thing, landing is also easy as can cut throttle to let it glide. Somehow I try to maiden it today n I crash it upon take off no damage but I dun understand the reason why it crashed. It flew up n start to take a right turn n dip down. I did counter back but dun know why it just cont n crashed. Am I not ready for this? Am I over-ambitious?

[joe yap]

This is my take; practice, practice and more practice. Also, practice objectively instead of blindly.

Forget about Funjets and stick to your trainer. If you trainer got written off, buy the new trainer again, and preferbly the same model and same setup if they work well you with. Your eyes only see 2 dimensional images in simulators but your eyes see 3 dimensional in real life. Learn how to use visual cues like the surrounded trees and buildings from far, to help you judge your flightpath, instead of tunnel visioning and staring at your model.

For every flying session, plan ahead and formalise a 'lesson plan' before flying, instead of just zipping across the sky aimlessly. Keep the model type, the setup and everything else simple and consistant. Stick to proven setups that works well with you all the time so that you can focus on your 'flying lessons' without too many distractions.