1.3 % Sign in a London Bus
 

What does it mean ?

It's on one of the new double decker busses as you enter
at the front, on the left, under the windscreen.

There is a headlight sign and 1.3 %.

I asked the driver with predictable results.

First correct answer gets a cracker jack pencil.

--
Klaatu

Gort! Deglet Ovrosco!

1.3 % Sign in a London Bus
 

On Thu, 20 Nov 2003 18:21:08 +0000, Klaatu
wrote:

What does it mean ?

It's on one of the new double decker busses as you enter
at the front, on the left, under the windscreen.

There is a headlight sign and 1.3 %.

Something to do with the angle of the dipped headlamp beams, I think,
but I couldn't be totally sure.

Neil

--
Neil Williams
is a valid email address, but is sent to /dev/null.
Try my first name at the above domain instead if you want to e-mail me.

1.3 % Sign in a London Bus
 

If u look on any vechile you will find this. its to do with the aim of the
headlights to avoid dassileing othere road uses


"Klaatu" wrote in message
...
What does it mean ?

It's on one of the new double decker busses as you enter
at the front, on the left, under the windscreen.

There is a headlight sign and 1.3 %.

I asked the driver with predictable results.

First correct answer gets a cracker jack pencil.

--
Klaatu

Gort! Deglet Ovrosco!

1.3 % Sign in a London Bus
 

Rob wrote:
"Klaatu" wrote in message
...
What does it mean ?

It's on one of the new double decker busses as you enter
at the front, on the left, under the windscreen.

There is a headlight sign and 1.3 %.

I asked the driver with predictable results.

First correct answer gets a cracker jack pencil.

If u look on any vechile you will find this. its to do with the
aim of the headlights to avoid dassileing othere road uses

Perhaps 1.3% is the percentage of words you spell correctly?
:-)

Seriously, you are right. See official diagram at
http://www.hmso.gov.uk/si/si1989/Uks..._en_28.htm#end

The requirement is specified at
http://www.hmso.gov.uk/si/si1989/Uks...n_9.htm#(4i)i2
See paragraph 12(b).

--
Richard J.
(to e-mail me, swap uk and yon in address)

1.3 % Sign in a London Bus
 

"Richard J." wrote in message
...
Rob wrote:
"Klaatu" wrote in message
...
What does it mean ?

It's on one of the new double decker busses as you enter
at the front, on the left, under the windscreen.

There is a headlight sign and 1.3 %.

I asked the driver with predictable results.

First correct answer gets a cracker jack pencil.

If u look on any vechile you will find this. its to do with the
aim of the headlights to avoid dassileing othere road uses

Perhaps 1.3% is the percentage of words you spell correctly?
:-)

Seriously, you are right. See official diagram at
http://www.hmso.gov.uk/si/si1989/Uks..._en_28.htm#end

The requirement is specified at
http://www.hmso.gov.uk/si/si1989/Uks...n_9.htm#(4i)i2
See paragraph 12(b).

I wonder what that figure of 1.3% actually *means*. It's a strange way to
specify what is really an angle between the horizontal and the beam. I
presume that 1.3% equates to arctan(1.3/100) or 0.75 degrees. I suppose it's
done like that because the easiest way to check the setting is to position
that vehicle a known distance (eg 10 metres) from a vertical wall and
measure the vertical offset (eg 1.3% of 10 = 0.13 metres) of the beam from
the straight-ahead position of the headlamp.

I notice that the regs don't mention that headlamps usually dip leftwards as
well as downwards - or at least they don't stipluate the amount of
horizontal offset.

1.3 % Sign in a London Bus
 

On Fri, 21 Nov 2003 11:45:50 -0000, "Rob" wrote:

If u look on any vechile you will find this. its to do with the aim of the
headlights to avoid dassileing othere road uses


And the 1.3 % means ?

--
Klaatu

Gort! Deglet Ovrosco!

1.3 % Sign in a London Bus
 

On Thu, 20 Nov 2003 18:57:04 GMT, (Neil
Williams) wrote:

On Thu, 20 Nov 2003 18:21:08 +0000, Klaatu
wrote:

What does it mean ?

It's on one of the new double decker busses as you enter
at the front, on the left, under the windscreen.

There is a headlight sign and 1.3 %.

Something to do with the angle of the dipped headlamp beams, I think,
but I couldn't be totally sure.

Yes, I think we can take that as a given. It's the 1.3 % bit though.

--
Klaatu

Gort! Deglet Ovrosco!

1.3 % Sign in a London Bus
 

I wonder what that figure of 1.3% actually *means*. It's a strange way to
specify what is really an angle between the horizontal and the beam. I
presume that 1.3% equates to arctan(1.3/100) or 0.75 degrees.

Certainly when measuring road and railways grades the percentage is either
the tangent or the sine, depending on who you ask. Consensus favours the
tangent as being more correct but with the sine being used in practice
because it can be easier to measure and there is beggar all difference in
practical terms for slopes shallower than around ten to fifteen degrees
anyway.


I suppose it's
done like that because the easiest way to check the setting is to position
that vehicle a known distance (eg 10 metres) from a vertical wall and
measure the vertical offset (eg 1.3% of 10 = 0.13 metres) of the beam from
the straight-ahead position of the headlamp.

Seems reasonable and also is probably correct.

1.3 % Sign in a London Bus
 

On Fri, 21 Nov 2003 12:26:22 GMT, "Martin Underwood"
wrote:

"Richard J." wrote in message
...
Rob wrote:
"Klaatu" wrote in message
...
What does it mean ?

It's on one of the new double decker busses as you enter
at the front, on the left, under the windscreen.


Seriously, you are right. See official diagram at
http://www.hmso.gov.uk/si/si1989/Uks..._en_28.htm#end

The requirement is specified at
http://www.hmso.gov.uk/si/si1989/Uks...n_9.htm#(4i)i2
See paragraph 12(b).

I wonder what that figure of 1.3% actually *means*. It's a strange way to
specify what is really an angle between the horizontal and the beam. I
presume that 1.3% equates to arctan(1.3/100) or 0.75 degrees. I suppose it's
done like that because the easiest way to check the setting is to position
that vehicle a known distance (eg 10 metres) from a vertical wall and
measure the vertical offset (eg 1.3% of 10 = 0.13 metres) of the beam from
the straight-ahead position of the headlamp.

Excellent - Thanks

--
Klaatu

Gort! Deglet Ovrosco!

1.3 % Sign in a London Bus
 

The requirement is specified at
http://www.hmso.gov.uk/si/si1989/Uks...n_9.htm#(4i)i2
See paragraph 12(b).

I wonder what that figure of 1.3% actually *means*. It's a strange way to
specify what is really an angle between the horizontal and the beam. I
presume that 1.3% equates to arctan(1.3/100) or 0.75 degrees. I suppose it's
done like that because the easiest way to check the setting is to position
that vehicle a known distance (eg 10 metres) from a vertical wall and
measure the vertical offset (eg 1.3% of 10 = 0.13 metres) of the beam from
the straight-ahead position of the headlamp.

Excellent - Thanks

And if your'e wondering what kind of obssesive mind you need to think
of theses thing:

Bi weekly I meet a mate and we go to a Jam night in a pub. QED no
driving as beers are consumed. Once the 1.3 % sign had been noticed
once, well that was it.
--
Klaatu

Gort! Deglet Ovrosco!