Trail Strike Again...

[jrtubb]

So I'm trying to get better with my B450 3D but seems like I keep coming down too hard and touching the tail blades, which of course results in replacement parts. I finally brought my B450 out to my club field to get some more space to fly in vs my backyard and was doing ok until I got pushed out of sorts by a wind gust. I reduced cyclic, but it dropped too fast and bang broken parts. This is the only damage I ever do to this helicopter, I've replaced the parts 4 times now. I didn't want to go metal since I'm afraid it will move the damage up the chain to more expensive items.

Any advice? The throttle and pitch curves are stock, seems to drop fast to me with little movement of the left stick (full CP mode). I have the larger wider Align Gear so I don't fly with training gear, but maybe I need to go back to it to protect the tail assembly.

[puppydog_taz]

The simple answer is you need to come down slower! What kind of pitch curve are you running in normal flight mode? You should only have about 3 degrees of negative pitch with the collective all the way down in normal flight mode.

[ManInAGarden]

Are you flying with a non flat throttle curve setting?

I had a quite similar experience with my 450-3D. Got too low in a slightly banked curve and I was not able to save the heli by applying more pitch because I flew with a throttle curve with 0 at the low stick position. Rotor speed was too low to recover fast from that situation. Many broken parts and two days on the workbench were the result of that.

From this incident on I decided to fly with a flat throttle curve and a pitch curve from -10deg to +10deg only. With a flat throttle curve rotor speed is mostly constant and you get more thrust in virtually no time. I start and land with that setting (no switching during flight). I never had to regret this by now.

[jrtubb]

Honestly I'm not sure about either as all I have done is set up the 450 to my DX6i per the manual settings. I'll look a bit later tonight

[ManInAGarden]

Originally Posted by jrtubb

Honestly I'm not sure about either as all I have done is set up the 450 to my DX6i per the manual settings. I'll look a bit later tonight

In the manuals I found two different settings for advanced and intermediate pilots. I used to have the one for intermediate pilots. This one has two modes (normal and stunt) of which I always used the normal mode (upper switch on left front of DX6) which has a throttle curve starting at zero throttle. That was the "bad" curve and I supect that you're also using this one.

[Gladius]

How tight are your tail blades? They should be just tight enough that they don't fall under their own weight. That way, they will give a little if they touch the ground, and you'll get less broken parts. I'm a big fan of the baby-auto landing. It lets you come down without applying power to your blades, again lessening the effects of a tail strike. Finally, what surface are you landing on? Asphalt is really hard on tail blades, so if you can, land on grass.

[andycrazy]

Do you have a sim? Using a sim is good way to practice taking off, hovering and landing. Landings need to be practiced as much as any other skill so you will learn how to bring your heli in nice and level with minimum skid bounced and NO tail strikes. Gdet used to bringing the heli into a hover about 2feet (60cm) off the ground and level before landing in all orientations (except inverted).

I found that the Throttle Curves listed in the manual cause the Heli to drop around 6ft (2m) when changing from normal to stunt mode (idle up). I used a flat throttle curve at 80 in normal and 100 in stunt with Pitch curve set 0, 25, 50, 75, 100 in all modes. DR start at 60/20 in normal and 85/20 stunt rising to 85/20 normal and 100/20 in stunt as I got used to it. The heli handling is more responsive and it has enough headspeed to pull out of dodgy manouvres.

I never could fly the heli in the intermediate mode as I found it too sluggish and unresponsive and I never got it off the ground with the training gear. Changed to the settings and pulled the training gear off and away I went!!! Also fitting 500 align landing gear will lessen any tendency to tip over when landing on uneven ground.

[sierracharlie]

For now try no more than a 0 to -3 neg pitch in normal. I also use an Align 500 skid. Here are my settings for slow upright flight using a DX6i.

Normal - TH 0, 25, 55, 68, 75. Pitch 50, 62, 75, 80, 85.
Stunt TH is 75, 75, 75, 75, 75. TH Hold TH 0. Pitch 50, 62, 75, 80, 85

D/R Expo - Aile 50% +25, Elev 40% +20; Rudd 40% +15

As long as it is not too windy you can fly fairly fast circuits.

Hope this helps.

[andycrazy]

Originally Posted by sierracharlie

For now try no more than a 0 to -3 neg pitch in normal. I also use an Align 500 skid. Here are my settings for slow upright flight using a DX6i.

Normal - TH 0, 25, 55, 68, 75. Pitch 50, 62, 75, 80, 85.
Stunt TH is 75, 75, 75, 75, 75. TH Hold TH 0. Pitch 50, 62, 75, 80, 85

D/R Expo - Aile 50% +25, Elev 40% +20; Rudd 40% +15

As long as it is not too windy you can fly fairly fast circuits.

Hope this helps.

From your pitch curves you have no negative pitch if the heli is set up correctly. You really need some negative pitch to help bring it down in windy conditions. Winds can either make the heli suddenly rise (negative pitch needed to keep control when this happens) or make it suddenly drop (positive pich and headspeed required to keep control when this happens). Flying fast circuits is easy on any CP heli, however flying with full control of the heli in any given situation and orientation is the most important skill to learn.

[jrtubb]

Thanks guys. I'm looking at my settings and in Stunt mode:
throttle curve is flat 80%
Pitch curve 45% 51% 60% 91%

I'm thinking about getting the Trex 600 gear and the 310 mm skids, I know I need to learn but I just want a bit of help. I practice on the simulators and do fine, real life is still different and takes practices.

[ManInAGarden]

While looking at your signature I can see that your journal of rc-helis is quite similar to mine. I had a Blade msR (though no X like you do) and from that small fixed pitch heli I directly went over to a Blade 450-3D. I felt that almost everything I learned with the fixed pitch helicopter was useless. But I kept practicing - crashing - repairing for quite some time. I also used a training gear in the beginning.

Then my thumbs learned how to fly (must be the famous muscle memory). For me there were three main moments up to now:

1. The moment I got rid of the trainig gear. Can't be too early in my option.
2. The moment I found out that I had to use idle up all the time and deleted all of my normal mode throttle and pitch curves and made kind soft stunt modes out of them with lower throttle but flat and a pitch range of -10 to +10.
3. The moment I found out how to fly banked turns on the simulator. That made it easy to fly circles and figure eights.

That's were I am now and I want to get into loops and rolls now. Works well on the simulator but first tries ended in crashes with my 130X. Hope my personal experiences can help you somehow.

[jrtubb]

Thanks, I don't like the training gear and have switched to the TREX 500 gear. Actually I bought a 500 gear at my LHS, looked real sporty, was wider but not any higher. Looking at people's 450 pictures I realized there was a standard 500 gear and a low one. I realized I had the low, which gives more no more tail clearance then stock. Last week I ordered the 500 standard gear and now have .75" clearance under the tail and still just as wide. So far I really like it and hope it helps with my tail strike issues. As a bonus I moved the low 500 gear to a SR I got cheap, so no training gear on her either.

Oh just to add salt to the wound, I was in the LHS this weekend playing on Phoenix simulator and totally kicking butt! Several people were impressed, but I just said I'm great in the PC world but not so much in real life.