RE: A real bunch of swell modelers... not

RE: A real bunch of swell modelers... not
View related threads: (in this forum | in all forums)

Logged in as Guest

Users viewing this topic: none

Printable Version

All Forums >> RC Airplanes >> M.A.A.C. >> RE: A real bunch of swell modelers... not Page: << < prev 1 2 3 [4] 5 next > >>

Login

Message

<< Older Topic Newer Topic >>

RE: A real bunch of swell modelers... not - 7/7/2005 12:59:41 PM

Jim_McIntyre

Posts: 2078
Joined: 4/5/2002
From: Claremont, ON, CANADA
Status: offline

quote:

ORIGINAL: britbrat
If it is so, is it confined to the burgeoning ARF world?

Not confined to, although I have witnessed many ARF failures due to poor contruction

quote:

ORIGINAL: britbrat
Perhaps it is a constant rate, but with numbers increasing due to greater involvement.

That could very well be. I think Ken hit that one with his reference ti "replaceable Patty". Adding to the problem (imho), If you have little "sweat equity" in the aircraft, you may be more inclined to test to destruction.

quote:

ORIGINAL: britbrat
I recently killed a very tired 10 yr old Ultra Sport 40 by stuffing it full of 60-size motor & trying to exceed 100 mph with it.

I've seen this too often, with the one difference that there was little regard to the safety of others.

quote:

ORIGINAL: can773
if you do a full throttle dive at the ground and haul in 30 degrees of elevator you cant expect your plane to survive long :-)

I've witnessed many variations of this. Most common is the overpowered ARF performing a full throttle snap, literally resulting in the snapping off of the tail. Often blamed on poor quality ARF construction, I blame it on lack of throttle management. The "burning holes in the sky" mentality seems to have tracked along with the growing popularity of ARFs.

Overall, I see a decline in disciplined flying (co-ordinated turns, throttle management smooth maneuvers etc.)

_____________________________

http://scalebuilder.org

(in reply to britbrat)

Post #: 76

RE: A real bunch of swell modelers... not - 7/7/2005 2:49:54 PM

can773

Posts: 1642
Joined: 1/25/2002
From: Calgary, AB, CANADA
Status: offline

quote:

ORIGINAL: Jim_McIntyre

quote:

ORIGINAL: can773
if you do a full throttle dive at the ground and haul in 30 degrees of elevator you cant expect your plane to survive long :-)

I've witnessed many variations of this. Most common is the overpowered ARF performing a full throttle snap, literally resulting in the snapping off of the tail. Often blamed on poor quality ARF construction, I blame it on lack of throttle management. The "burning holes in the sky" mentality seems to have tracked along with the growing popularity of ARFs.

Overall, I see a decline in disciplined flying (co-ordinated turns, throttle management smooth maneuvers etc.)

What!, you mean you are supposed to use the left stick? Damn.....thats surely why I have not yet won the Worlds LOL. Coordinated turns?! What the heck? Thats why we use differential!

Further to your comment on throttle management....if you intend on doing such insane manuvers such as full throttle blenders your plane needs to be capable of performing such tasks....otherwise the design is flawed for intended purpose....Nothing wrong with not using the throttle as long as your plane is built to deal with that...otherwise she is garbage bin material :-)

_____________________________

Chad Northeast

(in reply to Jim_McIntyre)

Post #: 77

RE: A real bunch of swell modelers... not - 7/7/2005 3:47:28 PM

Jim_McIntyre

Posts: 2078
Joined: 4/5/2002
From: Claremont, ON, CANADA
Status: offline

But ... that is the problem ... very few ARFs (with some high dollar exceptions) are built to withstand this kind of abuse (especially when over-engined) for any extended period. That's what I was referring to when I alluded to the consumeable airframe (edible Patty?

) Ken brought up.

As for differential, I doubt any but the most competitive flyers comprehend, let alone bother to set up differential throws or any other advanced setup like fin offsets, static or dynamic counter-balancing etc etc.. Heck, I bet the majority who have radios capable of conditions use them for anything other than setting up a "landing mode".

_____________________________

http://scalebuilder.org

(in reply to can773)

Post #: 78

RE: A real bunch of swell modelers... not - 7/7/2005 4:38:46 PM

britbrat

Posts: 3299
Joined: 6/15/2004
From: Deep River, ON, CANADA
Status: offline

Jim, do you have any statistics to go with your concern, or is this a gut-feeling thing, based upon your personal observations?

(in reply to Jim_McIntyre)

Post #: 79

RE: A real bunch of swell modelers... not - 7/7/2005 5:23:15 PM

Jim_McIntyre

Posts: 2078
Joined: 4/5/2002
From: Claremont, ON, CANADA
Status: offline

No stats, just one man's observation ... albeit, an observation from someone who lives within 30 minutes of 7 clubs with an average membership of ~80 and who has enjoyed attending many events over many years...

I'm not here to say the sky is falling, just noting a potentially dangerous trend and wondering if other have observed the same. Is it widespread or localised?

_____________________________

http://scalebuilder.org

(in reply to britbrat)

Post #: 80

RE: A real bunch of swell modelers... not - 7/7/2005 5:33:50 PM

jhelps

Posts: 163
Joined: 1/9/2003
From: Headingley, MB, CANADA
Status: offline

While I can't confirm all that Jim say's it has been my experience that there are folks who use their computer radios to compensate for poorly built or set up aircraft (mixing throttle with rudder remove poor fin alignment over a broad speed range, or to correct improper engine thrust offset). It is after all so much easier to slap a servo in each wing and use the computer functions to set up differential (if folks do it at all) and direction than it is to use one servo with pushrods and bell cranks.

One of my first futaba radios did not have servo reversing. You got 1 servo that ran the other way and had to use it wisely.

I fly both helicopters and twins and make use of many of the computer features but by no means all. I have also observed a number of times where computer radios led to a crash because:

A) the wrong aircraft was selected on multiple model mode radio's; or
B) complex programming led to the wrong switch or function being activated at the wrong time.

Personnally for my B-25 twin I have a printed checklist with startup - takeoff - emergency- and landing procedure checks whcih include reminders for switch settings, which my apotter reads to me as required. (I have toyed with the idea of installing a gyro to give me some automatic yaw control in an engine out situation, but haven't followed up on it yet).

Jeff

(in reply to britbrat)

Post #: 81

RE: A real bunch of swell modelers... not - 7/7/2005 6:25:37 PM

Jim_McIntyre

Posts: 2078
Joined: 4/5/2002
From: Claremont, ON, CANADA
Status: offline

Another error I see far too often related to computer radios is the use of travel volumes (or end point adjustments or any of the other terms that mean roughly the same) to compensate for bad geometry, resulting in loss of granularity of control.

Another is the use of sub trims or digital trims to avoid adjusting the clevis, resulting in undesireable asymetric throw.... but this often goes unnoticed by the "burn holes in the sky" type.... as long as it snaps.

_____________________________

http://scalebuilder.org

(in reply to jhelps)

Post #: 82

RE: A real bunch of swell modelers... not - 7/7/2005 10:51:55 PM

can773

Posts: 1642
Joined: 1/25/2002
From: Calgary, AB, CANADA
Status: offline

quote:

ORIGINAL: jhelps

While I can't confirm all that Jim say's it has been my experience that there are folks who use their computer radios to compensate for poorly built or set up aircraft (mixing throttle with rudder remove poor fin alignment over a broad speed range, or to correct improper engine thrust offset). It is after all so much easier to slap a servo in each wing and use the computer functions to set up differential (if folks do it at all) and direction than it is to use one servo with pushrods and bell cranks.

One of my first futaba radios did not have servo reversing. You got 1 servo that ran the other way and had to use it wisely.

I fly both helicopters and twins and make use of many of the computer features but by no means all. I have also observed a number of times where computer radios led to a crash because:

A) the wrong aircraft was selected on multiple model mode radio's; or
B) complex programming led to the wrong switch or function being activated at the wrong time.

Personnally for my B-25 twin I have a printed checklist with startup - takeoff - emergency- and landing procedure checks whcih include reminders for switch settings, which my apotter reads to me as required. (I have toyed with the idea of installing a gyro to give me some automatic yaw control in an engine out situation, but haven't followed up on it yet).

Jeff

Jeff

The throttle to rudder mix is not a bandaid for a bad setup its a solution to physics.....fin offset, thrust offset only work at a certain speed, certain AOA and certain throttle setting......outside that range those built in adjustments are incorrect.....I have used this mix and while I prefer to control the change in yaw manually I know of a number of top guys (Chip Hyde for one) who use this mix on a regular basis......

Same goes for differential electronically....I can do it faster and more accurately with my TX than anyone can with a mechanical setup.....all my throws are measured to less than 1/10 of a degree in every direction and on every surface.

Use the TX to give you all of its potential otherwise you have just wasted your money.....personally I use 3 different rudder to elevator mixes, throttle to elevator mix, snap conditions, spin conditions, landing condition to get the plane always doing what I want it to.....

Although its possible to use the features incorrectly and have poor results....but used properly they give you amazing potential.

< Message edited by can773 -- 7/7/2005 10:53:33 PM >

_____________________________

Chad Northeast

(in reply to jhelps)

Post #: 83

RE: A real bunch of swell modelers... not - 7/8/2005 2:14:30 AM

jhelps

Posts: 163
Joined: 1/9/2003
From: Headingley, MB, CANADA
Status: offline

Chad

I agree with your comments. My post was mostly about the folks that use it as a panacea for poor building or repairs in the first place. Poorly set engine offset is something that I see very often as a problem, in fact I had it myself in an own designed airplane. The plane would snap at the top of a loop. Spent quite a bit of time adjusting and re-adjusting the thrust line until it was perfect. Would have been an interesting computer set up to mix rudder and aileron for various speed ranges.

Am NOT advocating push rods and bellcranks, however spending a bit of attention at the build stage, can reduce the need to "mix" the problems out.

(in reply to can773)

Post #: 84

RE: A real bunch of swell modelers... not - 7/8/2005 1:19:44 PM

Jim_McIntyre

Posts: 2078
Joined: 4/5/2002
From: Claremont, ON, CANADA
Status: offline

quote:

ORIGINAL: can773
Use the TX to give you all of its potential otherwise you have just wasted your money.....

I don't see anyone saying not to use the features of the radio (I use a lot of mixes myself). I think the points being made here are that using the Tx to compensate for poor construction (as Jeff points out) or poor mechanical setup (as I was referring to) is all too common.

For example, when I'm asked to help out with a setup, the most common errors I find are:

digital trims at or near max deflection
control horns not at 90 degrees
servo travel ridiculously attenuated

and, my favourite, aileron trim offset to compensate for a rudder out of trim.

_____________________________

http://scalebuilder.org

(in reply to can773)

Post #: 85

RE: A real bunch of swell modelers... not - 7/8/2005 1:56:06 PM

britbrat

Posts: 3299
Joined: 6/15/2004
From: Deep River, ON, CANADA
Status: offline

While I am in no way advocating sloppy mechanical set-ups, is there any supportable evidence that the use of radio capabilities to nullify poor geometry/set-up actually causes crashes, or increaes the frequency of crashes? There will always be poorly set-up models & models that have been crashed and are no longer straight -- but they still fly, & fly in control.

We are discussing an alledged increase in crash frequency -- is it real? If so, is it caused by poor configuration & set-up, or poor construction, or poor training or bad attitudes?

I doubt if the use of radio capabilities to offset airframe deficiencies causes more crashes per pilot now than it did ten yrs ago.

I also doubt that models are now more poorly built -- I believe that, if anything, they are better built because ARFs are generally better than a plan-built model that a newbie can turn out.

Show me the bodies & why they are there -- then I will consider accepting that there is a problem.

(in reply to Jim_McIntyre)

Post #: 86

RE: A real bunch of swell modelers... not - 7/8/2005 2:14:57 PM

can773

Posts: 1642
Joined: 1/25/2002
From: Calgary, AB, CANADA
Status: offline

quote:

ORIGINAL: Jim_McIntyre

quote:

ORIGINAL: can773
Use the TX to give you all of its potential otherwise you have just wasted your money.....

I don't see anyone saying not to use the features of the radio (I use a lot of mixes myself). I think the points being made here are that using the Tx to compensate for poor construction (as Jeff points out) or poor mechanical setup (as I was referring to) is all too common.

For example, when I'm asked to help out with a setup, the most common errors I find are:

digital trims at or near max deflection

control horns not at 90 degrees

servo travel ridiculously attenuated

and, my favourite, aileron trim offset to compensate for a rudder out of trim.

Those are the extreme cases for sure, and I would agree in that sense.....but I would never hold anyones radio setups to the same standard that I hold my own....

If your servo is 1 spline off 90 it doesnt matter....if you use 10-20% of ATV to fix something it really doesnt matter.

Would you call using a dual rate set to 30% rediculous? I do it, many others do it.....I would not have done it 5 years ago.....but with the servos we have today they are so accurate that even at those low numbers nothing is lost (maybe in theory but not in practise)........How else do you go from 6 degrees deflection to 22?

As long as your plane is setup mechanically sound.....I say do as you please with the radio (even using subtrims, which we do

) The only important thing is that the throw deflection is equal after you have made your changes.

Have I witnessed these things causing crashes? Not personally.....I am sure there are a number of crappy radio setups at the field but most of the guys care very little if their plane tracks perfect through a loop....so in their mind their radio setup is fine which is ok with me :-)

_____________________________

Chad Northeast

(in reply to Jim_McIntyre)

Post #: 87

RE: A real bunch of swell modelers... not - 7/8/2005 2:58:23 PM

Jim_McIntyre

Posts: 2078
Joined: 4/5/2002
From: Claremont, ON, CANADA
Status: offline

quote:

ORIGINAL: can773
Those are the extreme cases for sure...

They may be extreme but, all too common. So common, I look for them first when someone asks me to help with a setup.