Cross WInds

[Danos]

I'v never been so interested in the weather since taking up flying. Today was a weird one so i decided to land. Yesterday 12mph winds floating like a bird real nice. Today 4mph winds with a crosswind what worried me was a couple of times i actually felt as if i lost contact with the glider it didnt repsond until i made a severe banking manoever. She actually flew better yesterday with the tree tops shaking. Yesterday seemed so simple upwind downwind landing was a breeze.Ive changed transmitter battery but is it possible the cross wind made it feel as if i had no control until i did that severe move with the stick. Itd also very cloudy can that effect my range? I under stand im touching on a broad subject to many possibilties.

Flying Weather advise is what im looking for as i will be checking electrical side fo things. Cheers

Dan.

Edited By Danos on 10/04/2013 11:37:13

[Garry Pollard]

Hi Dan

The trick with landing with a cross wind is to use RUDDER as the primery control. Most peeps dont and make a hash of the landing Also as far as I know cloud will not affect TX range at all

It would however help if you described what controls you were using for the landing

Garry

[Olly P]

Garry - I think wha Dan is saying is that the aircraft appeared to need a bigger input to respond than yesterday, and is not sure why.

[Martin Harris - Moderator]

You may (and should) have been approaching with a higher airspeed in the headwind. If the model appeared to be flying at the same groundspeed it was actually at up to 12 mph slower which would affect the control responses significantly.

[Danos]

Hi thanks for replying good to know clouds nto a factor Olly is right about me needing a bigger input it felt for a few secs she wasnt responding to my inputs i panicked and did a full left bank and then i felt i had control back. This happened twice. The question could the crosswind make it appear as if it isnt responding? And jus in 4mph? When yesterday in 12mph it was real easy there was no crosswind yesterday. Thanks

Dan

[PatMc]

Posted by Garry Pollard on 10/04/2013 11:55:58:

Hi Dan

The trick with landing with a cross wind is to use RUDDER as the primery control. Most peeps dont and make a hash of the landing Also as far as I know cloud will not affect TX range at all

It would however help if you described what controls you were using for the landing

Garry

Using the rudder as primary control during landing is a recipe for disaster. In fact unless you can use it fully co-ordinated with aileron it's best not used at all during landing until the wheels are in contact with the ground.

[Danos]

That makes sense Martin i had slowed down i keep aborting landings cus im not happy with airspeed or stabilty crosswind etc i pulled up with throttle gained some altitude cut off motor banked to make anuva approach thats when i started getting the loss of control i talk of. (possible stall?)This tends to makes things worse for me as i end up crashing. Ive started dreading landings never used to be a problem haha

Thanks

Dan

[Danos]

I dont actually have rudder control it may sound weird to you guys but i dont like rudder control it gets in my way while applying throttle plus i love alerons and with this model its all about weight so one less servo is gd for me.

[PatMc]

Danos, only the airspeed will have an effect on the control reponsiveness. The direction the model is flying with relation to the wind has no effect. It's most likely that you inadvertantly fed in some up elevator because the groundspeed made the model appear to be flying faster than you wanted.

[Garry Pollard]

Posted by PatMc on 10/04/2013 13:46:58:

Posted by Garry Pollard on 10/04/2013 11:55:58:

Hi Dan

The trick with landing with a cross wind is to use RUDDER as the primery control. Most peeps dont and make a hash of the landing Also as far as I know cloud will not affect TX range at all

It would however help if you described what controls you were using for the landing

Garry

Using the rudder as primary control during landing is a recipe for disaster. In fact unless you can use it fully co-ordinated with aileron it's best not used at all during landing until the wheels are in contact with the ground.

You fly your way, and I will fly my way. One crash in 6 yrs flying, will keep me flying my way, and that was due to a faulty lipo

Garry

[Steve Hargreaves - Moderator]

Remember that "wind" is just a mass of air moving relative to the ground...the model isn't concious of "wind" at all; it is just flying in air. The problem is that you are on the ground so all your perceptions of the model are related to the ground.

As Martin alludes in his post the groundspeed of the model changes dramatically depending on if the model is travelling with the wind or against it & this is the speed you can see your model moving at.

As an example...say the model flys at an airspeed of 30mph......in still air you would notice no difference in its speed around a typical circuit. Now lets assume a wind of 10mph. As the model travels with the wind it will appear to you to be moving at 40mph.....as it turns & heads into wind it will appear to you to have slowed down to 20mph. In fact neither is true as far as the model is concerned...its still doing 30mph through some air.

Now, because this un-nerves us we try & correct the speed difference we can see so we try & slow the model down when travelling with the wind & this is dangerous.....the model appears now to be traveling at 30mph but actually has an airspeed on 20mph......this can make it seem very sluggish on the controls. Conversely we try & speed the model up when flying into wind.....we want it to be travelling at 30mph but this is an airspeed of 40mph so the controls feel nice & crisp.

Now, crosswind turns.....again the model doesn't know or care that there is a cross wind but as you try & turn cross wind the model is blown along relative to you stood on the ground & this can make it seem to be taking a long while to come around....particularly so on rudder/elevator models. The problem is excaserbated if you have just been travelling downwind....you probably slowed the model down as explained above & now you are trying to turn it with soggy controls whilst it is being blown away from you.....you start to panic & pull in more elevator to tighten the turn....oh dear....you have just exceeded the wings max AoA & stalled.....hope you were high enough to recover.....

The trick here is to accept that the model will sometimes look to be doing strange things in the air relative to the ground but it probably isn't.....keeping a good constant airspeed is key here....start your crosswind turns a bit earlier to allow for the drift & I'm sure you'll start to feel a bit more confident & in control....

I'm also intruiged by your comment "downwind landing was a breeze" We usually land INTO wind as this reduces the speed the model hits the ground....usually a good thing!!

[cymaz]

Buy a really cheap sim that plugs into your Tx. Then you can practice as much as you like and no harm done by changing the parameters

[PatMc]

Garry, if you want to fly your way that's entirely up to you but passing on bad advice isn't in anyones interests.

[Danos]

SOrry STeve it wasnt meant to be read that way my English is terrible what i meant was it was easy to distinguish where the uphill and downwinds were AND landings were easy. With the crosswinds i felt as tho i was all over the place. I always launch and land into the wind. Great bit of info steve i will keep that in mind for future flights in fact i shud be heading out in an hours time. Oh and yes i was high enuff to get out of the stall i landed safely i was just aboit unnerved as ive had a few crashes lately lol. Cymaz i might invest in one can practice when weathers poor.

Cheers guys

Dan

[Martin Harris - Moderator]

Posted by PatMc on 10/04/2013 14:23:34:

Garry, if you want to fly your way that's entirely up to you but passing on bad advice isn't in anyones interests.

I'm with Pat on this.

Consider the classic spin entry...

Raise the nose to reduce speed allowing the model to slow progressively and at the point of stall, apply rudder in the direction you wish to spin

...so a landing approach where you are slowing towards the point of stall in air which is likely to be turbulent is not the best place to be departing from balanced flight!

The only time un-coordinated flight in the circuit is appropriate is in a slipping approach or at the point of rounding out during a crabbed one.

[Danos]

Thankyou guys for explaining in so much detail i'll certainly take onboard whats been said.

Dan

[Steve Hargreaves - Moderator]

H'mmm interesting thinking Martin.....I have to admit my understanding was always to pick up a low wing during landing with the rudder. Doing so with the ailerons effectively increases the AoA by lowering the control surface on the low wing thus making it more prone to stalling.

When landing cross wind of couse we apply some rudder to keep the nose pointing slightly into wind until just before touchdown when a thumbful of opposite rudder aligns the fuselage with the direction of travel.....

[Ponty Bri]

As a full size aircraft pilot I chose to keep the aircraft into wind, which sometimes meant watching the runway out of the side window, then you can keep the plane on track and at the last minute before touchdown kick it straight with a bootfull of rudder and level the wings with ailerons. Timing is everything.

Brian

[PatMc]

Steve, Martin has it spot on. In a crosswind approach the model should be pointing slightly (depending on wind strength, direction & model's airspeed) into wind with the wings held level by the ailerons. The rudder shouldn't be applied until touch down, or at a height where a stall would just drop it gently onto the ground without damage.

[will -0]

When landing cross wind of couse we apply some rudder to keep the nose pointing slightly into wind until just before touchdown when a thumbful of opposite rudder aligns the fuselage with the direction of travel.....

Oh lordy, well if that works for you then that's fine but if you'll be flying sideways all the way down the approach which makes a spin more probable if you stall.

 

The "correct" way is to use ailerons to steer into wind sufficiently to keep the track of the aircraft aligned with the desired runway and then use the rudder at the last minute to align the wheels with the ground. This is so much easier to do if you're sat in the aircraft and actually a bit tricky to do perfectly with a model.

Edited By will -0 on 10/04/2013 16:40:43

[will -0]

PS Danos, it's quite common to see people think they have loss of [radio] control when actually they are just going too slowly for the [aerodynamic] controls to work. Generally the slower [airspeed] you go the less well they'll work and of course as you approach the stall, ailerons generally stop working completely [although you'll probably see some "3d" aircraft for which that is not true]. The ultimate one is where people claim they had a radio glitch as their aircraft is spinning into the ground because they've got far too slow.

It's also worth remembering that the aircraft is not affected by groundspeed, only airspeed. Hence if it's going into a 10mph headwind at what looks to you like 10mph (groundspeed) it's actually doing 20mph airspeed. Similarly if you're going downwind at what looks to you like 10mph and it has a 10mph tailwind it will have 0 mph airspeed and won't be flying at all. On windy days aircraft can seem much more twitchy. Sometimes this is because turbulence is throwing them around, but it is often because we're flying them faster.

Edited By will -0 on 10/04/2013 16:53:28

Edited By will -0 on 10/04/2013 17:04:25

[Danos]

Wow i like this site ask a question get tonns of advice  Thanks

Edited By Danos on 10/04/2013 18:25:25

[Phil Claridge]

my models are not affected by wind, i feed them rennies

[Danos]

I have started doing stunts n stuff im definatly pushing my boundaries shame theres no model club where i live

[Danos]

lOL pHIL

Edited By Danos on 10/04/2013 18:23:39