How fast will flies fly?

DaveB

The weather is heating up and the flies are out which really annoy the
hell out of me on long climbs. On these long climbs I've had plenty of
time to come up with a theory.

My theory is that (all brontosauruses are thin at one end ...sorry
couldn't resist) flies are only prepared to fly at 13kmh to land on me.
If I'm going 14kmh I'm not worthy of chasing and they leave me alone. Of
course that only applies if there's no wind. Anyone else noticed this?
How about a measurement to identify how stinky you are, eg. so stinky
flies will still follow you at 17kmh

DaveB

jazmo

Riding behind another rider on Beach rode a few weeks back, between him and me was a fly spoiling my slipstream. We would have been doing 30 - 35 km/h. Was an interesting sight watching a fly hovering between the both of us.

Boostland

"DaveB" <dbuerckner@NOSPAMMOgmail.com> wrote in message
news:474f7045$0$14416$afc38c87@news.optusnet.com.au...
> The weather is heating up and the flies are out which really annoy the
> hell out of me on long climbs. On these long climbs I've had plenty of
> time to come up with a theory.
>
> My theory is that (all brontosauruses are thin at one end ...sorry
> couldn't resist) flies are only prepared to fly at 13kmh to land on me. If
> I'm going 14kmh I'm not worthy of chasing and they leave me alone. Of
> course that only applies if there's no wind. Anyone else noticed this? How
> about a measurement to identify how stinky you are, eg. so stinky flies
> will still follow you at 17kmh
>
> DaveB

Some interesting stuff here about the aussie bush fly and others.

http://www.viacorp.com/flybook/fulltext.html

"Wind speed. Another surprising one: strong winds don't make bush flies less
pesky. They bother you almost as much on a windy day as on a still one.
Winds speeds of 36 km/hr and more were common in one set of experiments, but
it didn't keep the flies grounded -- or off people. But note this: though
bush flies take to the air on a windy day, they get blown downwind. Relative
to the air, they fly pretty slowly (about 8 km/hr, top speed)."

ray

Boostland wrote:
> "DaveB" <dbuerckner@NOSPAMMOgmail.com> wrote in message
> news:474f7045$0$14416$afc38c87@news.optusnet.com.au...
>> The weather is heating up and the flies are out which really annoy the
>> hell out of me on long climbs. On these long climbs I've had plenty of
>> time to come up with a theory.
>>
>> My theory is that (all brontosauruses are thin at one end ...sorry
>> couldn't resist) flies are only prepared to fly at 13kmh to land on me. If
>> I'm going 14kmh I'm not worthy of chasing and they leave me alone. Of
>> course that only applies if there's no wind. Anyone else noticed this? How
>> about a measurement to identify how stinky you are, eg. so stinky flies
>> will still follow you at 17kmh
>>
>> DaveB
>
> Some interesting stuff here about the aussie bush fly and others.
>
> http://www.viacorp.com/flybook/fulltext.html
>
> "Wind speed. Another surprising one: strong winds don't make bush flies less
> pesky. They bother you almost as much on a windy day as on a still one.
> Winds speeds of 36 km/hr and more were common in one set of experiments, but
> it didn't keep the flies grounded -- or off people. But note this: though
> bush flies take to the air on a windy day, they get blown downwind. Relative
> to the air, they fly pretty slowly (about 8 km/hr, top speed)."
>
>
Fly Speed (assuming no strong wind from any direction) is as above, 17
k/mh or thereabouts. However, as is well known, they will hang onto your
back whilst moving and then swarm as soon as you slow down or stop.
Short of spraying your shirt and knicks with Aerogard I don't see
there's much you can do about it.
Cheers,
Ray

TimC

On 2007-11-30, ray (aka Bruce)
was almost, but not quite, entirely unlike tea:
> Fly Speed (assuming no strong wind from any direction) is as above, 17
> k/mh or thereabouts. However, as is well known, they will hang onto your
> back whilst moving and then swarm as soon as you slow down or stop.
> Short of spraying your shirt and knicks with Aerogard I don't see
> there's much you can do about it.
> Cheers,

Eat more kangaroo.

http://www.smh.com.au/news/letters/...l?page=fullpage

As you can see, I write letters to the editor about really important
issues facing the nation, on election day.

--
TimC
I repeat myself when under stress. I repeat myself when under
stress. I repeat myself when under stress. I repeat myself when
under stress. I repeat myself when under stress. I repeat myself
when under stress. I repeat myself when under stress. I repeat

Halcyon

>>
> Fly Speed (assuming no strong wind from any direction) is as above, 17
> k/mh or thereabouts. However, as is well known, they will hang onto your
> back whilst moving and then swarm as soon as you slow down or stop.
> Short of spraying your shirt and knicks with Aerogard I don't see
> there's much you can do about it.
> Cheers,
> Ray
Yes, 17kph seems to be the figure. I recall reading once that at the
CSIRO Baseline Air Testing station at Cape Grim on the very NW tip of
Tassie that they don't have any flies because the winds average over
17kph from the west(there's a lot of ocean to the west)and the flies get
blown away. No doubt someone can confirm this or otherwise.
Halcyon

coppershark

I have always found that about 20kph was enough to keep the flies off, which supports the 17kph figures quoted.

Mike