It's happening! Um... sort of.

On Mon, 26 May 2014 10:41:30 -0400, Frank Krygowski
wrote:

On 5/26/2014 7:46 AM, John B. wrote:
On Sun, 25 May 2014 22:51:30 -0400, Frank Krygowski
wrote:

On 5/25/2014 4:20 PM, Phil W Lee wrote:
Frank Krygowski wrote:

I've wondered a bit about the commercial airplane effect. It seems to
me that the incremental effect of one passenger is negligible. IOW, if
one person chooses not to buy a ticket, the plane will fly anyway with
one more empty seat (assuming all else is equal). The fuel saving would
seem to be negligible.

Actually, air travel is one area where empty seats do save a
considerable amount of fuel - far more than is the case with
ground-based transport.

Explain, please. It looks like 750,000 pounds is a reasonable value for
a large airliner's total weight. One potential passenger who stayed
home reduces that by far less than 0.1%. How much fuel is actually saved?

Large aircraft calculate takeoff weight dependant on the empty
aircraft weight, the weight of cargo and the distance that they have
to fly. This gives them their gross weight for take off.

A 747-400, I believe, can carry something like 500,000 pounds of fuel
and something like 189,000 pounds of cargo, and has a maximum gross
weight for take off of 987,000 lbs. if we deduct the total fuel and
cargo weight we get an empty weight of something like 300,000 lbs.

Now suppose that our flight required 4 hours of flight time and we are
only carrying 90,000 lbs of cargo. To make this mission we will
require less power to maintain cruising speed because the airplane is
lighter. If we load maximum cargo and fuel, right up to the maximum
permitted weight for take off then the fuel consumption will be much
higher.

The actual calculation for max gross weight for take off is a bit more
complicated as runway lengths as well as altitude and temperature and
even dew point is also taken into consideration.

I understand that lower weight implies less fuel use by the plane. My
question was whether a one-passenger reduction (by a conscientious
objector to air travel who skips a flight) makes any significant - or
even detectable - difference. I suspect that unless a flight is
canceled, the fuel use is essentially the same; and that many people
must cancel their tickets to get a flight canceled.

I doubt that the addition or subreacti0n of one person, say 0.09% of
the cargo load, would have a measurable effect. As I said elsewhere a
bit more frequent washing would likely have a larger effect.

But, I believe that airlines must fly their routes and schedules
whether loaded or empty. I don't remember where I read that but I
think it is part of being granted a route.

Then we have to wonder about the alternatives, assuming those folks did
need to get to where the flight was going. According to
http://en.wikipedia.org/wiki/Environ...t_of_transport
it seems like air travel generates between 0.18 - 0.24 kg CO2 per
passenger mile. Cars, perhaps 0.35; long-distance buses perhaps 0.08,
and trains about 0.19 kg/passenger-mile.

If those figures are correct, then replacing one's air travel with
anything other than a bus trip could be a net loss.

(Walking or bicycling would be much more benign, of course; but then,
nobody considers bicycling and air travel to be realistic competitors
for the same journey.)

Or perhaps a sailing vessel.
"In 1850, with seven vessels taking part and large amounts of money
riding on the outcome. The vessel "Samuel Russel" took 109 days to
reach San Francisco from New York, shortening the existing record by
eleven days, and creating a sensation that was hard to overcome."
--
Cheers,

John B.
(invalid to gmail)

On 5/26/2014 2:35 PM, Joe Riel wrote:
Duane writes:

On 5/26/2014 12:32 PM, Joy Beeson wrote:
On Mon, 19 May 2014 17:39:20 -0400, Frank Krygowski
wrote:

Motorists seem to think "He's over the line, so there's no way he'll
ever cross it."

With bike lanes, you have the additional thought: "He's in the magic
safe zone. As long as my tires have part of their tread on my side of
the line, and his tires are on his side of the line, everything is
fine. I don't have to worry about my door handle or his knuckles."


And without the bike lane the motorist is going to worry about my
knuckles? Sorry but not the case in my experience.

Remove the line and an uncertainty arises, which, in my experience,
gives larger passing distances.

I strongly agree.

--
- Frank Krygowski

On 5/26/2014 3:36 PM, Dan O wrote:
On Monday, May 26, 2014 11:35:51 AM UTC-7, JoeRiel wrote:
Duane writes:
On 5/26/2014 12:32 PM, Joy Beeson wrote:
On Mon, 19 May 2014 17:39:20 -0400, Frank Krygowski wrote:

Motorists seem to think "He's over the line, so there's no way he'll
ever cross it."

With bike lanes, you have the additional thought: "He's in the magic
safe zone. As long as my tires have part of their tread on my side of
the line, and his tires are on his side of the line, everything is
fine. I don't have to worry about my door handle or his knuckles."

And without the bike lane the motorist is going to worry about my
knuckles? Sorry but not the case in my experience.

Remove the line and an uncertainty arises, which, in my experience,
gives larger passing distances.

That is consistent with my experience, too.

However, the uncertainty is not all upside. Anxiety is not
the ideal basis for social interaction.

Forester says bike lanes are meaningless because they are where
you should ride anyway when being passed, and that exceptions to
the requirement to use them make the situation too difficult for
people to understand.

What's to understand? Ride in a way that makes sense (move left
to set up for a left turn, go around right turning traffic on the
left, keep right to allow faster traffic by on your left, avoid
hazards, negotiate for shared space). Cars stay out of the bike
lane.

It sounds easy to understand. But I think most people don't understand
it. Most cyclists won't leave a bike lane to avoid door zones. Many
think the stripe somehow protects them from right hooks. Many motorists
think bikes don't matter at all, so bike lane equals parking lane. Many
traffic design staffers don't understand that bikes are often much safer
away from the road edge.

This is, in part, why education is needed, even if there is a magic
stripe on the road.

Not enough space for your comfort? Ride somewhere else. Duh.

I've seen three-foot-wide bike lanes, with the rightmost 1.5 feet being
the concrete curb apron. Most cyclists think they may never leave that
three foot zone, even though it's not enough room.

Maybe we can get the incompetent designers to add paint saying "Ride
somewhere else. Duh."

--
- Frank Krygowski

On 5/26/2014 8:39 PM, Phil W Lee wrote:
Frank Krygowski considered Sun, 25 May 2014
22:51:30 -0400 the perfect time to write:

On 5/25/2014 4:20 PM, Phil W Lee wrote:


Actually, air travel is one area where empty seats do save a
considerable amount of fuel - far more than is the case with
ground-based transport.

Explain, please. It looks like 750,000 pounds is a reasonable value for
a large airliner's total weight. One potential passenger who stayed
home reduces that by far less than 0.1%. How much fuel is actually saved?

On a long-haul flight (taking a transatlantic flight as typical
"long-haul), about twice the weight of the passenger and their luggage
will be saved in fuel. It used to be more (about 25% more in a 747),
but modern aircraft are slightly more fuel efficient.
It varies rather, depending on aircraft type, load factor (the first
few passengers don't cost as much in fuel as the last few, for
example, as fuel consumption graphs curve upwards more steeply with
increased weight*, rather than being a straight line), cruising
altitude, and even where on the aircraft the passengers are (or would
have been) loaded, but it's a fair approximation of the average
saving.

So if we take as an average a passenger + baggage weight of 100Kg
probably a touch conservative, these days), the average fuel cost on a
transatlantic light is going to be in the region of 248.75 litres,
based on Jet A1 having a density of 0.804kg/L.

You may think that's insignificant - but it would keep my car in fuel
for a couple of years.

I don't doubt the results of the calculation, but I imagine it's still a
negligible percentage of what the plane consumes for that trip.

And then there's the problem of finding an alternative. For a
transatlantic flight, the alternatives are very few, and very
unpalatable for most people. Practically speaking, if that fuel
consumption is not to be accepted, you're telling almost everyone they
may never travel that route.

I believe it was Mayer Hillman who predicted that at some time in the
future, each person will be allotted a carbon budget at birth. Use it
as you like, but it would have to last you all you life. If that comes
true, it will certainly restrict travel for all but those wealthy enough
to buy others' allotments.


--
- Frank Krygowski

On 27/05/14 11:19, Frank Krygowski wrote:
On 5/26/2014 3:36 PM, Dan O wrote:


It sounds easy to understand. But I think most people don't understand
it. Most cyclists won't leave a bike lane to avoid door zones. Many
think the stripe somehow protects them from right hooks. Many motorists
think bikes don't matter at all, so bike lane equals parking lane. Many
traffic design staffers don't understand that bikes are often much safer
away from the road edge.

This is, in part, why education is needed, even if there is a magic
stripe on the road.

Not enough space for your comfort? Ride somewhere else. Duh.

I've seen three-foot-wide bike lanes, with the rightmost 1.5 feet being
the concrete curb apron. Most cyclists think they may never leave that
three foot zone, even though it's not enough room.

Maybe we can get the incompetent designers to add paint saying "Ride
somewhere else. Duh."


It seems the POMs are beginning to reject **** infrastructure.

http://www.cycling-embassy.org.uk/ne...al-cycle-paths

--
JS

On Monday, May 26, 2014 6:41:38 PM UTC-7, Frank Krygowski wrote:

snip

And then there's the problem of finding an alternative. For a
transatlantic flight, the alternatives are very few, and very
unpalatable for most people. Practically speaking, if that fuel
consumption is not to be accepted, you're telling almost everyone they
may never...

You really should see someone about that all-or-nothing
thinking.

... travel that route.

I believe it was Mayer Hillman who predicted that at some time in the
future, each person will be allotted a carbon budget at birth. Use it
as you like, but it would have to last you all you life. If that comes
true, it will certainly restrict travel for all but those wealthy enough
to buy others' allotments.

Why in such a world would some people be wealthier than others?

On Monday, May 26, 2014 6:19:16 PM UTC-7, Frank Krygowski wrote:
On 5/26/2014 3:36 PM, Dan O wrote:
On Monday, May 26, 2014 11:35:51 AM UTC-7, JoeRiel wrote:
Duane writes:
On 5/26/2014 12:32 PM, Joy Beeson wrote:
On Mon, 19 May 2014 17:39:20 -0400, Frank Krygowski wrote:

Motorists seem to think "He's over the line, so there's no way he'll
ever cross it."

With bike lanes, you have the additional thought: "He's in the magic
safe zone. As long as my tires have part of their tread on my side of
the line, and his tires are on his side of the line, everything is
fine. I don't have to worry about my door handle or his knuckles."

And without the bike lane the motorist is going to worry about my
knuckles? Sorry but not the case in my experience.

Remove the line and an uncertainty arises, which, in my experience,
gives larger passing distances.

That is consistent with my experience, too.

However, the uncertainty is not all upside. Anxiety is not
the ideal basis for social interaction.

Forester says bike lanes are meaningless because they are where
you should ride anyway when being passed, and that exceptions to
the requirement to use them make the situation too difficult for
people to understand.

What's to understand? Ride in a way that makes sense (move left
to set up for a left turn, go around right turning traffic on the
left, keep right to allow faster traffic by on your left, avoid
hazards, negotiate for shared space). Cars stay out of the bike
lane.

It sounds easy to understand. But I think most people don't understand
it. Most cyclists won't leave a bike lane to avoid door zones. Many
think the stripe somehow protects them from right hooks. Many motorists
think bikes don't matter at all, so bike lane equals parking lane. Many
traffic design staffers don't understand that bikes are often much safer
away from the road edge.

Sounds like education gets an 'F'.

This is, in part, why education is needed, even if there is a magic
stripe on the road.

Well, it *would* be, if the stripe weren't magic ;-)

No, education *is* needed (for some riders - maybe most - should
be accessible to all). Which begs the question, if education is
feasible, why not have some bike lanes? Is it really just for
the street sweeper action of sharing space with car traffic?

Not enough space for your comfort? Ride somewhere else. Duh.

I've seen three-foot-wide bike lanes, with the rightmost 1.5 feet being
the concrete curb apron. Most cyclists think they may never leave that
three foot zone, even though it's not enough room.

Maybe we can get the incompetent designers to add paint saying "Ride
somewhere else. Duh."

Interesting you should mention that in the context of the need
for education *with* bike lanes. I've already mentioned how
the evolved bike lane design teaches riders to move away from
right-hook situations; and how in Portland the downhill bike
lanes leading to bike boxes were modified to include a warning
about right turning traffic in the bike lane. Both are examples
of education that is universally accessible and applicable.

On Monday, May 26, 2014 8:47:34 PM UTC-7, Dan O wrote:
On Monday, May 26, 2014 6:19:16 PM UTC-7, Frank Krygowski wrote:

snip

This is, in part, why education is needed, even if there is a magic
stripe on the road.

Well, it *would* be, if the stripe weren't magic ;-)

No, education *is* needed...

(Unfortunate phrasing that - please mind the comma. The "No"
negates the preceding facetious sarcasm. As in, "No, it's
*not* magic." And, "Yes, education *is* needed... ")

snip

On Mon, 26 May 2014 14:10:13 -0400, Duane
wrote:


And without the bike lane the motorist is going to worry about my
knuckles? Sorry but not the case in my experience.

Without the bike lane, the motorist is obliged to make his own
judgment.

The motorists on Western Avenue wouldn't budge an inch for me, and I
*did* get my knuckles rapped.

The motorists on State Farm gave me so much room that I was afraid
that they wouldn't be able to get back into their own lane before
someone going the other way came along.

THEY WERE THE SAME PEOPLE.

I became very familiar with the housing developments along Western
Avenue.

--
Joy Beeson
joy beeson at comcast dot net

On Monday, May 26, 2014 9:09:56 PM UTC-7, Joy Beeson wrote:
On Mon, 26 May 2014 14:10:13 -0400, Duane wrote:

And without the bike lane the motorist is going to worry about my
knuckles? Sorry but not the case in my experience.

Without the bike lane, the motorist is obliged to make his own
judgment.

The motorists on Western Avenue wouldn't budge an inch for me, and I
*did* get my knuckles rapped.

The motorists on State Farm gave me so much room that I was afraid
that they wouldn't be able to get back into their own lane before
someone going the other way came along.

THEY WERE THE SAME PEOPLE.

I became very familiar with the housing developments along Western
Avenue.

Using bike lanes is almost always less pleasant than riding
on a road with no bike lane. But that is because roads with
bike lanes are usually wider; and that is usually because they
carry more and faster traffic. On roads with lots of faster
traffic, the bike lane eases contention for space.

That super wide pass you mention on roads without bike lanes
is not very feasible on very busy roads with faster traffic,
now is it?

I generally prefer quieter roads, but can ride anywhere, and
sometimes the less pleasant route is better for my objective
(e.g. commuting). Bike lanes can make this less contentious
for everyone.

I often see people riding in the bike lane on a road that
really sucks, when I know of a *much* more pleasant (and
sometimes faster) route a block or two over. But they
either don't know about it, or maybe they *are* just
transportation bicyclists and haven't made the leap to
the joy of it ;-)

It's ironic that so many people who think riding a bike
in car traffic is too daunting, and that bike lanes will
alleviate this. It doesn't. But if this misconception
gets them out riding around, they are bound to discover
what's what. And if they are susceptible to the bug
that is the joy of riding a bike instead of driving a
car, they'll be hooked and on their way.

The VC'ers like to say how their approach enables riding
anywhere without facilities. That's fine. But bike lanes
open up more options by making even the busiest roads more
practicable without fouling up the works for everyone else.

(Not to mention the benefit of space reserved for filtering
forward through heavy traffic. It must be done carefully -
as would anything in heavy traffic, but there are some places
I can filter forward _multiple blocks_ past lines of cagers.)

So bike lanes are not desirable on most roads; but they are
a very good thing on some, and always will be, I think.

A better solution is a largely separate network of routes
for bikes, ala the awesomest bicycling societies. This is
not practical in the US yet, and we might even
wind up developing a whole new model as we evolve out of
our unprecedented car culture. We are different now than
any society has ever been, so it's hard to say where we'll
end up. But I suspect some of the more advanced communities
will start developing pockets of what looks more like The
Netherlands, Copenhagen, Cambridge, etc.

Meanwhile, yeah - using bike lanes is kind of like the
bicyclist's version of the automobile rat race. But at
least if you're on a bike, when you bail out of the rat
race, you're ready to roll in a more engaging fashion.