crashing

[Ernie]

Hi Guys,

From time to time, there is a query about a crash, and it's causes.  Usually there is a  multitude of advice, mainly good, but sometimes a wee bit iffy.

I wonder if it would be worthwhile for us to provide a logical procedure, to analyse the causes, and to suggest ways of preventing a similar problem in the future.

Just like the big boys do

 

ernie  

[Clive Matthews]

In my experience;

 

   1, Pilot error - loss of orientation

   2, Low volts to receiver

   3, Pilot error - fuel starvation

   4, Pilot error - distraction

   5, Structural failure

   6, Loss of radio link

 

 I think that the first thing to remember is not to turn the receiver off after a crash and check for any remaining radio function. If the pilot is honest with himself he will be able to identify the cause. Structural failure is often apparent prior to loss of control.

[David perry 1]

I did this years ago: I managed to get all the club chaps to fill in a crash log, for every signle crash over a summer. Then I analysed them into stage of flight, nature of weather etc.  It was a useful exercise.

 

I cant recall the actual outcomes now, but it was almost always pilot error: too slow, too fast, too much control etc.  Many people struggle to fly in strong winds because they confuse ground speed and airspeed -  I wrote an article for RCME about it and I see another one was published quite recently on the same subject, so it must be a perennial issue

 

The only crashes I have had in recent years have been caused by ejection of the nicad under high g loads, which is shameful I know but it happened.

 

The best bit of advice i ever received, years and years ago went like this; the guy had landed about two feet short and bitten the grassy verge. I said "oh bad luck". He turned right round and said "No, bad flying".

 

David

 

still trying to flog a H9 P51 and Saito 180 if anyone's interested.

[Bryce Allcorn - BritFlight.co.uk]

Mine are always pilot error/trying to do something stupid.

 

But I learn lessons, such as ensuring that the top of the wing is covered/coated/coloured after flying a prototype wing into my face. 

 

The only two that I can remember were not linked to specific pilot error was the time the motor fell of the mount on the HTWO-O (not secured properly) but still glided in for a perfect landing and flew again 10 mins later and the time a dog "caught" the HTWO-O while I was trying a low 'n' slow fly by.

 

Other than that it has been a result of hitting the ground at too steep and angle and at too high a speed...

[Simon Chaddock]

As a avid reader of the accident reports in the AAIB web site (how sad is that!) accidents (model or otherwise) fall into two basic categories - human error or technical failure.

 

As models fly for relatively short periods between at least a visual inspection we should not expect too many structural problems particularly as the strength to weight ratio of materials favours models.

For any RC by far the most complex and safety critical item is the control system. How many crashes result from some form of radio or servo failure?

 

My own crashes?

Radio twice (too low & too far away). Folded a wing (too fast & too many G).

Human error - all the rest!

[Clive Matthews]

I would hope that we suffer more structural problems than the 1/1 models

 

A lot of human error (human performance) in the 1/1s is a result of not recognising evidence. For example, ignoring the attitude indicator and relying on 'seat of pants' or as recently occured, failing to recognise a faulty speed indication leading to structural failure.

 

Unfortunately, we only have our own eyes for attitude and speed reference(for now at least). No excuse then

[Ernie]

Hi guys, 

So what about a check list for the newcomer?

ernie

[Andy Gates]

My take is that all crashes are the result of pilot error.

 

Using the examples above (sorry guys) 

 

1 Folded wing - pilot pulled too many G for the airframe

2 Folded wing - missed a fault in the structure during inspection (it was inspected?)

3 Radio failed - too low - pilot flew it too low but surely he could still see it?

4 Radio failed - too far away - who flew it so far away and could he still see it?

 

Loss of orientation

 

A pilot needs to recognise what has caused the loss in orientation.

Lack of light, working camoflage and poor vision are all major contributers.

These can be overcome with experience, or taking avoiding action (Specsavers for instance or lights on the plane)

 

Loss of Rx / Tx power

 

This has to be attributed as pilot error.

Either the charging scheme in use for battery maintainance is poor or voltage tests at the field were ignored. Broken or bad connectors fall under poor maintainance too as far as I am concerned.

 

Loss of flight power

 

While it can be an issue, a pilot of A cert standard should be able to regain the landing strip and land without incident. A crash due to loss of flight power is again pilot error.

 

Distraction

 

The only time this should be an issue is if noises are heard in the vicinity of the strip on late finals. Two choices - open up and go around, or a poorer choice is to have a glimps for the source of the noise and either abort or land. Again to my mind the visual check should have occured far earlier in the downwind leg before fully commiting to a landing.

 

Structural failure and  loss of radio link have already been dealt with.

 

So for me all crashes are the result of pilot error or a poor decission by the pilot.

 

My own mistakes?

 

Refitting a flat flight battery for a flight, done this twice now and have reviewed my system on each occasion.

Flying into stationary objects, I was doing circles around myself and a goal post with a small electric . As I turned round I slowly moved without realising it. Smashed a wing into the goal post.

[Biggles' Elder Brother - Moderator]

Well I have very fresh experience to bring to bear on this one - spent most of today repairing the damage from a crash yesterday afternoon.

Cause? Pilot error - 100%!

 

I was practising landing appraoches by flying overshoots. After two fairly highish attempts a I decided to make the next one a little lower. Crossed the strip threshold at about 5 feet, still decending. Opened up about 2 feet off, still decending! Too late, much too late! Result, I flew the plane at full throtle into the ground in a nose down attitude. Ouch! Lost the main undercart, firewall ripped out, underside of fuse badly damaged by collasping nosewheel and a broken prop.

 

The accident is unimportant - I can repair the damage. What I think is important are two things;

 

1. Being totally honest with myself about the cause. It was my fault, I had a plan - ie fly an overshoot - and I stuck to it even when the circumstances demanded a reappraisal of the situation!

 

2. Learn from the mistake! Don't do it again!

 

BEB

[Martin Harris - Moderator]

Well I can't see why the ground jumping up 6 inches and removing the radiator and both prop blades during a particularly low pass with my Dago Red could possibly be my fault...but I haven't trusted that runway since!

[Dusty]

Weather its your crafty a4 paper plane or your £2 grand beast it should have a dozen pre flight checks! A competent pilot will be able to handle a beast of  a plane if he has absolute confidence that the model strength, linkages,servos, powerplant, hinges etc etc are up to the job!

 

Pilot error and disorrentation is a factor too, but if its a commom cause for disaster then 1. you dont your plane 2. are not competant or secure safe/performing manovers with type 3. fly it like you getting your fittness up and ge used to it!

 

Dont fly so far away and high to aviod the above!

 

My 2p, yes  I have crashed enough planes to supply winters firewood with over the years ( i am not old either) but when you fly bigger models the same approach should be taken fot your smaller ones too... "no matches, I havent smashed a plank in 18months" I hope I aint jinxed now!