Passed My Observers Test!

Passed My Observers Test!

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markmullen

Original Poster:

15,877 posts

235 months

Monday 24th October 2005
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Sorry, nothing useful to add to the forum, just to say this afternoon I took my IAM Qualified Observers test (which TBH I didn't know I was about to take, I thought it was just an observed run in preparation) so in February when my local group gets its new intake I will be allocated an Associate to assist.

Best of all my local co-ordinator does tests for RoSPA so I am going to ask for assistance with doing their test and longer term want to do the HPC.

I think when it comes to my demonstration drive I will take a company car, not sure an LHD auto porker would set a good example :spin:

Kinky

39,576 posts

270 months

Tuesday 25th October 2005
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Nice one Mark.

Any comments on the test itself?

I assume in hindsight it was best you did not know it was the test?

K

dogwatch

6,231 posts

223 months

Tuesday 25th October 2005
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Yes, congratultions on your success!

BOF

991 posts

224 months

Tuesday 25th October 2005
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Well done Mark,

You might find it useful to have a notepad handy when at meetings or when driving with more experienced drivers or Examiners.

Note anything that you did not think of before, anything that might emphasise a point, stick in the mind of a new Associate, or need further investigation or practise on your part.

You do as much learning as teaching in the first few months...

BOF.

tonto

2,983 posts

249 months

Tuesday 25th October 2005
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Well done Mark.
I thought about doing this a couple of years ago, shortly after I passed my IAM test, (btw, this was in a Honda Integra type R. The Police Examiner was quite ammused and also quite impressed when I went for a 'brisk' overtake on my test!).
Let us know how you get on with your first Observer session.

Tony.

>> Edited by tonto on Tuesday 25th October 15:22

markmullen

Original Poster:

15,877 posts

235 months

Tuesday 25th October 2005
quotequote all
Thanks for the messages guys, the test went well, mostly thanks to my lack of preparation and hence no nerves.

I had to answer 30 questions, 10 on Roadcraft, 10 on the Highway Code and 10 on the intricacies of the Institute (our local group number etc).

I still have an issue having to remember stopping distances as I don't believe they are particularly relevant with modern braking systems.

I am looking forward to taking on an associate next year. In the meantime I may be doing the course unofficially with my mum!

BOF

991 posts

224 months

Tuesday 25th October 2005
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""I still have an issue having to remember stopping distances as I don't believe they are particularly relevant with modern braking systems""

That could be your first bit of research!

One of the things I tell my Associates is that the stopping distances are easy to remember - multiply by 2.5 - 3.5 - 4.5...so 30x2.5=75feet/50x3.5=175 feet/70x4.5=315 feet.

If you are Metric, work it out for yourself..the MOST important thing is that, if you are driving at 30 MPH and a child steps out 75 feet ahead of you, you will probably stop, maybe bruise the child.

If you are doing 40 MPH - same 75 feet when the kid steps out - you are still travelling at 27 MPH when you KILL the child.

Read up on the reasons for the stopping distances being as they are - modern braking sytems -bollox.

I am no good at physics, but thinking time + braking time with a ton of metal under your right foot does not change a great deal - it has been the subject of a lot of discussion - Google it?

More relevant today than ever, in my opinion...

BOF

>> Edited by BOF on Tuesday 25th October 21:39

volvos70t5

852 posts

230 months

Wednesday 26th October 2005
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BOF said:
if you are driving at 30 MPH and a child steps out 75 feet ahead of you, you will probably stop, maybe bruise the child.

If you are doing 40 MPH - same 75 feet when the kid steps out - you are still travelling at 27 MPH when you KILL the child.


And if a child presents itself in your path within your thinking distance there is no power on earth that is going to prevent an accident. That means that it is far more important to be driving at a speed where you can safely stop in the distance you can see to be clear rather than slavishly adhere to speed limits.

I am sure it is of absolutely no comfort to the parents of kids killed at or below the speed limit. Increased observation, is the key.

BOF

991 posts

224 months

Wednesday 26th October 2005
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Mark,

Here is a good article on braking...

BOF

www.ridedrive.co.uk/tipoffs03b.htm

woodytvr

622 posts

247 months

Wednesday 26th October 2005
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Ride Drive said:

THE CAR WILL NOT STOP ANY MORE QUICKLY THAN IT DID WITH THE STANDARD BRAKE COMPONENTS FITTED!


I'd have to disagree with this. There aren't many standard car brakes that can lock the wheels of a car over say 70.

Therefore it is logical if you can (by fitting modified brakes) bring the wheels to almost locking at anything over that speed they will infact stop a car quicker that is traveling over that speed.

>> Edited by woodytvr on Wednesday 26th October 17:35

7db

6,058 posts

231 months

Wednesday 26th October 2005
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I've tried emergency stops at 30 and 60. These are maximum threshold braking in the dry. I paced the result. At 60 it was about 30 yrds (maybe 35 allowing for uneven paces). At 30 it was closer to 1-2 car lengths (ie 6-8yrds)

Now this isn't anything like 75ft. How much of that is thinking distance?

StressedDave

839 posts

263 months

Wednesday 26th October 2005
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woodytvr said:

I'd have to disagree with this. There aren't many standard car brakes that can lock the wheels of a car over say 70.

Therefore it is logical if you can (by fitting modified brakes) bring the wheels to almost locking at anything over that speed they will infact stop a car quicker that is traveling over that speed.


I'd disagree with your disagreement. Back in the murky past when I was the Met Police Lab's official test drive I did a lot of very silly things with cars, one of which was skid testing them from elevated speeds (85 mph). To do this you have to lock the wheels instantaneously and then sit trying not to choke on the tyre smoke as you slide to a stop. I've yet to find a production car I couldn't lock the wheels on at 85 - it's a triumph of brutality over common sense. I was at an event last month where someone rode a Griffith 500 down to rest on locked tyres from 100 mph. That said, even if you do have shares in Yokohama, this isn't the way you or I actually go about slowing down - we dissipate the kinetic energy in the disk and pad rather than the tyre and tarmac.

The argument over fitting uprated brakes is to do with issues like fade and pedal feel rather than increasing the braking effort between pad and disc.

BOF

991 posts

224 months

Wednesday 26th October 2005
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7db/Volvo/woody

My post to Mark relates to IAM observing -not to track work - I have had Green Stuff pads on my motor for two years.

Whether they stop me quicker or would 'lock the wheels at over 70' is not relevant to the IAM, or to driving on public roads?

It is a 'given' that you should be able to stop within the distance that you can see to be clear - and a 'given' that speed limits are LIMITS not TARGETS.

7db - by your comment, you clearly understand that, in doing a planned emergency stop you have eliminated the thinking time that you would need - the DSA book states that thinking time at 30 is 9 meters/at 60 is 18 meters.

Do the distances allow for tiredness, drugged drivers,drunk drivers, sharp young drivers, old geezers like me, wet roads, illegal tyres, cars driven by folk who have walked through the Channel Tunnel, nicked a car, and who do not read English? - take your pick.

Borrowed from a Class 1 Traffic man...

' It's a traffic mans' phrase' - "At the end of a long set of skid marks, is usually a bunch of flowers"

BOF.

7db

6,058 posts

231 months

Wednesday 26th October 2005
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At 30mph:- 9m DSA thinking + 8yrds (above) stopping = 54ft. I think I'm missing 21ft somewhere, or 29% of the overall stopping distance.

I notice that 9m is 2/3s for thinking time. Does this include a bit for looking in the mirror, or reading the DSA handbook perhaps?

StressedDave

839 posts

263 months

Wednesday 26th October 2005
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The DSA thinking distance is a LOB for a start. It was picked so that it was 1 foot for each mph of speed - a nice easy number to remember. It correlates to a reaction time of about 0.67 seconds. In reality research suggests a typical reaction time is between 0.75 and 1.5 seconds.

The braking distance is based on a deceleration rate of about 0.68g. A locked wheel gives a deceleration rate of around 0.7g. At 30 mph it's very hard to lock the wheels under braking so you tend to get higher decelerations - leading to a shorter stopping distance. That's where your extra distance has gone.

BOF

991 posts

224 months

Wednesday 26th October 2005
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The '8 yards above' achieved by you, differs a wee bit from the DSA figure of 14 meters braking distance at 30mph.

No mention of looking in the mirrors - I expect it is just written for ordinary mortals, not drivers who can stop as quickly as you.

BOF.

Another good source...

www.driveandstayalive.com/info%20section/stopping-distances.htm

>> Edited by BOF on Wednesday 26th October 21:45

markmullen

Original Poster:

15,877 posts

235 months

Wednesday 26th October 2005
quotequote all
Thanks for the links guys, makes much more sense now.

I initially queried the stopping distances with my local IAM group who said "those are the distances because that is what the highway code says" even when I raised the issue of modern technology.

Also thanks for the formula for working them out, very useful.

woodytvr

622 posts

247 months

Thursday 27th October 2005
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StressedDave said:

woodytvr said:

I'd have to disagree with this. There aren't many standard car brakes that can lock the wheels of a car over say 70.

Therefore it is logical if you can (by fitting modified brakes) bring the wheels to almost locking at anything over that speed they will infact stop a car quicker that is traveling over that speed.



I'd disagree with your disagreement. Back in the murky past when I was the Met Police Lab's official test drive I did a lot of very silly things with cars, one of which was skid testing them from elevated speeds (85 mph). To do this you have to lock the wheels instantaneously and then sit trying not to choke on the tyre smoke as you slide to a stop. I've yet to find a production car I couldn't lock the wheels on at 85 - it's a triumph of brutality over common sense. I was at an event last month where someone rode a Griffith 500 down to rest on locked tyres from 100 mph. That said, even if you do have shares in Yokohama, this isn't the way you or I actually go about slowing down - we dissipate the kinetic energy in the disk and pad rather than the tyre and tarmac.

The argument over fitting uprated brakes is to do with issues like fade and pedal feel rather than increasing the braking effort between pad and disc.


What a cool job.

Did you ever find the point at which you couldn't lock up?

StressedDave

839 posts

263 months

Thursday 27th October 2005
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Nope - I'm still here to tell the tale, although one of my predecessors managed to break off the brake pedal on one celebrated occasion.

BOF

991 posts

224 months

Thursday 27th October 2005
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StressedDave said:
Nope - I'm still here to tell the tale, although one of my predecessors managed to break off the brake pedal on one celebrated occasion.


Dave...

""The argument over fitting uprated brakes is to do with issues like fade and pedal feel rather than increasing the braking effort between pad and disc.""

Pedal feel in my case - the Green Stuff pads seem to have a better 'bite' than the original pads, with the advantage of almost zero brake dust.

BOF