motorgliders as towplanes

On Fri, 20 Mar 2009 14:30:04 +0000, Jim Beckman wrote:

But it *does* make it the right answer to the written test when that
test is given by that same authority. For the test, concentrate not on
what is necessarily true, but on what the FAA wants for an answer.
After the written is out of the way, just learn to fly the aircraft.

Yes, and I learnt it as the answer to that Bronze question. It just
annoys me that official publications should enshrine myths as some sort
of truth.

Its no better than introductory texts showing packets of air dividing at
the LE of a ring and meeting up again at the TE, when a photo taken in a
wind tunnel shows clearly that doesn't happen. Far better to publish the
photo than a bogus diagram.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

On 21 Mar, 16:48, Martin Gregorie
wrote

Its no better than introductory texts showing packets of air dividing at
the LE of a ring and meeting up again at the TE, when a photo taken in a
wind tunnel shows clearly that doesn't happen. Far better to publish the
photo than a bogus diagram.

Oh, that one drives me mad. Not only does it not happen ... there is
no conceivable reason why it should happen. And yet many many websites
and books cite it as fact. Grrrrrrrrrrrrrrrrrr.

Incidentally, if you don't have a copy of "An Album of Fluid Motion"
by Milton Van Dyke, get it. You'll love it. Every gliding club should
have one.

Ian

On Sat, 21 Mar 2009 12:28:59 -0700, The Real Doctor wrote:

Incidentally, if you don't have a copy of "An Album of Fluid Motion" by
Milton Van Dyke, get it. You'll love it. Every gliding club should have
one.

Another recommendation:

http://www.av8n.com/how/ gives a good description of how an aeroplane
works. A lot of it is similar to "Stick and Rudder", so its written for
pilots rather than aircraft designers. However, section 3 has excellent
descriptions and diagrams showing how a wing works. It was recommended to
me by a professional aerodynamicist who is a model designer and has flown
gliders.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

On Sat, 21 Mar 2009 20:01:23 +0000, Martin Gregorie wrote:

On Sat, 21 Mar 2009 12:28:59 -0700, The Real Doctor wrote:

Incidentally, if you don't have a copy of "An Album of Fluid Motion" by
Milton Van Dyke, get it. You'll love it. Every gliding club should have
one.


Here's a link to animated visualizations of the flow past a wing:
http://www.av8n.com/irro/ - click the flag of your favored language to
see the visualizations.

--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

On 21 Mar, 20:18, Martin Gregorie
wrote:
On Sat, 21 Mar 2009 20:01:23 +0000, Martin Gregorie wrote:
On Sat, 21 Mar 2009 12:28:59 -0700, The Real Doctor wrote:

Incidentally, if you don't have a copy of "An Album of Fluid Motion" by
Milton Van Dyke, get it. You'll love it. Every gliding club should have
one.

Here's a link to animated visualizations of the flow past a wing:http://www.av8n.com/irro/- click the flag of your favored language to
see the visualizations.

I've never really liked that Joukowski transform stuff. The arbitrary
definition of circulation worries me, and anyway no real wing behaves
anything like that. It's a fair way of visualising the flow, roughly,
but I prefer to jump straight into circulation theory and model my
wings as vortices.

Ian

On Sat, 21 Mar 2009 16:01:33 -0700, The Real Doctor wrote:

On 21 Mar, 20:18, Martin Gregorie
wrote:
On Sat, 21 Mar 2009 20:01:23 +0000, Martin Gregorie wrote:
On Sat, 21 Mar 2009 12:28:59 -0700, The Real Doctor wrote:

Incidentally, if you don't have a copy of "An Album of Fluid Motion"
by Milton Van Dyke, get it. You'll love it. Every gliding club
should have one.

Here's a link to animated visualizations of the flow past a
wing:http://www.av8n.com/irro/- click the flag of your favored language
to see the visualizations.

I've never really liked that Joukowski transform stuff. The arbitrary
definition of circulation worries me, and anyway no real wing behaves
anything like that. It's a fair way of visualising the flow, roughly,
but I prefer to jump straight into circulation theory and model my wings
as vortices.

You're way beyond me there. I can choose suitable, matched wing and tail
sections for competition free flight models, which requires some
understanding of Rn effects and the usual section performance diagrams
and data. I also know a little about the use of turbulators and tip
shapes. As I've ended up with decently performing and stable, flyable
models I must be doing something right. However, thats as far as I go.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

That is a VERY good reference!!!

Mike Schumann

"Martin Gregorie" wrote in message
...
On Sat, 21 Mar 2009 12:28:59 -0700, The Real Doctor wrote:

Incidentally, if you don't have a copy of "An Album of Fluid Motion" by
Milton Van Dyke, get it. You'll love it. Every gliding club should have
one.

Another recommendation:

http://www.av8n.com/how/ gives a good description of how an aeroplane
works. A lot of it is similar to "Stick and Rudder", so its written for
pilots rather than aircraft designers. However, section 3 has excellent
descriptions and diagrams showing how a wing works. It was recommended to
me by a professional aerodynamicist who is a model designer and has flown
gliders.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |