Today's Message Index:
----------------------
1. 04:11 AM - Re: Re: Contact detail & Help (Frans Veldman)
2. 06:51 AM - pitot/static port cover? (Frans Veldman)
3. 07:00 AM - Re: Re: Contact detail & Help (David Joyce)
4. 07:08 AM - Re: pitot/static port cover? (David Joyce)
5. 07:41 AM - Re: Re: Pitot/static port cover. (Mike Gamble)
6. 07:44 AM - Re: pitot/static port cover? (Max Cointe)
7. 08:40 AM - Re: pitot/static port cover? (Robert Borger)
8. 09:35 AM - Re: Re: Contact detail & Help (Paul McAllister)
9. 10:11 AM - bonding fuselage top (Paul & Vanessa Munford)
10. 10:54 AM - Re: bonding fuselage top (David Joyce)
11. 11:23 AM - Re: bonding fuselage top (Pete Lawless)
12. 01:01 PM - Re: pitot/static port cover? (klinefelter.kevin@gmail.com)
13. 01:25 PM - Re: bonding fuselage top (craig)
14. 01:30 PM - Re: DOTH Haverford West mid-day or maybe Aberporth (graeme bird)
15. 03:55 PM - Re: Re: DOTH Haverford West mid-day or maybe Aberporth (Bob Harrison)
16. 04:02 PM - Re: bonding fuselage top (Bob Harrison)
17. 06:54 PM - Re: pitot/static port cover? (rparigor@suffolk.lib.ny.us)
Message 1
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| Subject: | Re: Contact detail & Help |
On 06/10/2012 06:21 AM, Bud Yerly wrote:
> If I do say so myself, I never have cooling issues in Florida at 95
> degree summer days using 50/50 Anitifreeze. Judging by the calls and
> email success stories, these simple techniques work pretty much world wide.
Although your solution might indeed work world wide it is less suitable
for Europeans.
There are a few reasons for this:
1) Your solution is focussed on more cooling air flow. Unfortunately
more cooling air also means more cooling drag. More cooling drag means
that higher power settings are required to achieve a desired cruise
speed. Although that might not be significant for those living in a part
of the world where fuel prices are only a fraction from what it is here,
for many of us here the fuel price is by far the largest cost involved
with flying our Europa's.
In another posting you wrote:
"135 with the old pants at 5500/34 inches at 1000 MSL,"
"His trigear only goes 130 at max cruise."
I do 130 with 27", about 155 with 34". This is a heavy hi-top tri-gear.
Although I selected a very efficient prop and have Fred Kleins wing root
fairings, I believe that a large portion of the reduction in drag is
achieved by my modified cooling system.
2) Climate. I believe that in your area the weather is somewhat more
constant than it is here. This month I have been flying in cruise mode
in freezing temperature conditions (high altitude in Norway) and in
prolonged full power climbs with 35C OAT (Croatia). Unless you use
thermostats you can't achieve constant temperatures in all conditions.
After numerous experiments this is what I have learned:
0) Cooling drag is the main drag of modern efficient airplanes. Imagine
the air swirling around in the cowling, colliding in all kind of
obstacles, and flowing over tubular objects (worst airodynamic shape
possible) and finally leaving the airplane in the wrong direction and
with the wrong speed...
1) The Rotax engine is for 95% liquid (oil, coolant) cooled. Forget
about airflow over the engine, apart from the cylinder walls no cooling
air is needed at all. Sure you can compensate for a poor liquid cooling
with air flow, but it is extremely inefficient. Once you have the liquid
cooling working correctly, you can close off all holes. That's right,
ALL holes. This includes the two "eye's". the gills, the naca inlets,
the nose wheel opening, everything. There is only one small opening
needed to connect the Rotax shroud for cylinder wall cooling.
2) The main problem in the stock setup is the radiator. The stock
radiator is too thick (not even to mention the tandem design). The
pressure difference required to maintain enough air flow is too large,
and you need very large openings to keep enough air flowing. I have
tried many carefully designed diffusers but I never got the stock
radiator working sufficient enough for prolonged full power climbs in
hot weather.
3) Use an oil to water heat exchanger. This means that you have to focus
on the air flow of only one radiator, and also don't need an oil
thermostat and still have superfast warm-up times.
4) Get away with the entire "dog house". It is ugly and it serves no
purpose.
5) Use an adjustable cowl flap to control engine temperatures.
6) Reroute the exhaust so the cowl opening points to the rear. I tried
to build an exhaust augmentor but I'm not sure if it really works. In
any case, the cowling air escaping around the exhaust opening flows in
the correct direction and doesn't upset the air stream.
So. what I'm using now is a thin radiator, mounted flush with the
underside of the cowling. (Custom made, 300 Euro's). It is slanted so it
follows the shape of the cowling. Because of the angle the horizontal
frontal area is very small, you can say it forms a natural diffuser.
Flow is controlled by an exit cowl flap. If the air flow is restricted
by the cowl flap, the air in front of the radiator even doesn't "see"
the radiator, the air flows over the surface and follows the shape of
the cowling as if the radiator doesn't exist at all.
The air leaving the radiator is recycled because it flows under the
engine, taking the heat of exhaust and turbo with it on its way out. No
separate openings for these items are necessary.
The coolant is also used to cool (or heat!) the oil via a heat
exchanger. Apart from the heat-up time, the oil temperature is always 5C
higher than the coolant temperature, which I consider to be perfect. I
keep the water at 105C and the oil at 110C in all conditions. This is
the best for the engine and the efficiency.
For cylinder cooling you can use the standard Rotax shroud with the
opening under the propeller. I made my own shroud because of the vaccuum
pad alternator which prevents the use of the standard shroud, but the
idea is similar.
After one year of using this, I can state the following results:
1) Adequate cooling in ALL conditions. I have excecuted a full power
climb from 0ft to FL095 at 80 knots in an inversion layer with a OAT of
35C for most of the trajectory, with the water temp not exceeding 110C
and the oil not exceeding 120C. This was with the cowl flap not yet
fully open. Although not yet tested, I'm convinced that the cooling
would work ok in OAT's of 45C as well.
2) In cruise the cowl flap is typically only half an inch open; i.e. it
protrudes only a half inch below the belly of the airplane. Compare that
with the huge tunnelexit of the stock XS design!
3) Unlimited ground operations, even in very hot weather.
4) Superfast heat-up times. 5 minutes is even in the winter sufficient
to get the oil temp far enough up into the yellow arc to perform a take off.
5) Low cowling temperatures, despite the lack of ventilation.
Temperatures don't exceed 60C, except briefly after engine shut off. In
hot weather I open the oil tank access door after landing for a few
minutes to let the hot air out.
6) Weight savings. I have not weighed the difference, but I'm sure the
flat radiator and heat exchanger is lighter than the two stock radiators
and tunnel hard ware.
About the picture:
This was the unfinished design. The final version is even smoother.
The only exit opening here is the proptrusion of the "tunnel" against
the belly of the fuselage. The nose wheel opening is sealed off and
flush with the belly. The cowl flap can be extended further but this is
the typical cruise setting. Quite a difference compared to the stock
tunnel, eh?
In addition of the rectangular radiator opening I have two round inlets.
The one on the starboard side serves the intercooler for the turbo (via
a wedge diffuser and butterfly valve). You don't need this inlet if you
don't have an intercooler. The opening on the port side connects to the
cylinder wall shrouds. You could use the standard Rotax shroud with the
opening below the prop instead, but I made a round inlet on the port
side to maintain the symmetry. In most setups you can ommit these round
inlets. That would be an even cleaner nose!
The starboard inlet also facilitates the engine air intake. The port
inlet also connects to a very small auxilliary oil radiator. Without
this radiator the water-oil delta T was 10C, and with the extra radiator
I got my desired delta T of 5C. It is not really needed if you are
satisfied with the standard delta T.
On the top of the firewall you see a small servo, a similar model as the
vertical trim servo. This servo connects via a rod to the cowl flap. The
cowl flap hinges close to the radiator so even when it is fully open the
angle is very low. A simple but very efficent mechanism!
The front exhaust elbows are wrapped to save the cowling which is very
close.
If there is enough interest in this subject, I'm willing to write an
article about it. There is a lot of testing, reading, thinking, and
learning from failures behind this design.
Although I have been flying a year with it now, I have only recently
been able to test it in very hot and demanding conditions during our
just finished round trip in Corsica, Italy and Croatia and overflying
the Alps twice.
More about that trip later.
Frans
Message 2
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| Subject: | pitot/static port cover? |
Hi,
On our recent trip to Croatia we left the aircraft for two days on a
very hot airfield. When we came back to depart we discovered that the
ASI was reading 70 knots... (Luckily our pitot system is air tight
otherwise we would have discovered it during our take off run or later).
Investigation (which is no fun on a very hot tarmac without shadow)
revealed that the pitot tube was internally sealed off by some
substance. Even poking and moving with a piece of wire inside the pitot
it was not possible to get air flow through it, despite all the stuff
that came out. Whatever was in there was even past the 90 degree bend.
Some insect had made a whole nest or something inside the tube.
I finally had to take the pitot/static assembly out to get it cleaned
with compressed air.
To avoid this in the future I would like to use a pitot cover, but in
the past I could never find a standard cover that fits, so after many
hours without a cover I thought I could live without one. Clearly not.
So, has anyone found some suitable standard cover or do I need to make
something myself?
Frans
Message 3
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| Subject: | Re: Contact detail & Help |
Frans, I for one and I am sure the entire Europa Club
committee would love to see you write an article for the
Europa Flyer detailing your design and flying findings.
Regards, David Joyce, G-XSDJ
On Wed, 20 Jun 2012 14:04:55 +0200
Frans Veldman <frans@privatepilots.nl> wrote:
> On 06/10/2012 06:21 AM, Bud Yerly wrote:
>
>> If I do say so myself, I never have cooling issues in
>>Florida at 95
>> degree summer days using 50/50 Anitifreeze. Judging by
>>the calls and
>> email success stories, these simple techniques work
>>pretty much world wide.
>
> Although your solution might indeed work world wide it
>is less suitable
> for Europeans.
>
> There are a few reasons for this:
> 1) Your solution is focussed on more cooling air flow.
>Unfortunately
> more cooling air also means more cooling drag. More
>cooling drag means
> that higher power settings are required to achieve a
>desired cruise
> speed. Although that might not be significant for those
>living in a part
> of the world where fuel prices are only a fraction from
>what it is here,
> for many of us here the fuel price is by far the largest
>cost involved
> with flying our Europa's.
>
> In another posting you wrote:
> "135 with the old pants at 5500/34 inches at 1000 MSL,"
> "His trigear only goes 130 at max cruise."
>
> I do 130 with 27", about 155 with 34". This is a heavy
>hi-top tri-gear.
> Although I selected a very efficient prop and have Fred
>Kleins wing root
> fairings, I believe that a large portion of the
>reduction in drag is
> achieved by my modified cooling system.
>
> 2) Climate. I believe that in your area the weather is
>somewhat more
> constant than it is here. This month I have been flying
>in cruise mode
> in freezing temperature conditions (high altitude in
>Norway) and in
> prolonged full power climbs with 35C OAT (Croatia).
>Unless you use
> thermostats you can't achieve constant temperatures in
>all conditions.
>
> After numerous experiments this is what I have learned:
> 0) Cooling drag is the main drag of modern efficient
>airplanes. Imagine
> the air swirling around in the cowling, colliding in all
>kind of
> obstacles, and flowing over tubular objects (worst
>airodynamic shape
> possible) and finally leaving the airplane in the wrong
>direction and
> with the wrong speed...
> 1) The Rotax engine is for 95% liquid (oil, coolant)
>cooled. Forget
> about airflow over the engine, apart from the cylinder
>walls no cooling
> air is needed at all. Sure you can compensate for a poor
>liquid cooling
> with air flow, but it is extremely inefficient. Once you
>have the liquid
> cooling working correctly, you can close off all holes.
>That's right,
> ALL holes. This includes the two "eye's". the gills, the
>naca inlets,
> the nose wheel opening, everything. There is only one
>small opening
> needed to connect the Rotax shroud for cylinder wall
>cooling.
> 2) The main problem in the stock setup is the radiator.
>The stock
> radiator is too thick (not even to mention the tandem
>design). The
> pressure difference required to maintain enough air flow
>is too large,
> and you need very large openings to keep enough air
>flowing. I have
> tried many carefully designed diffusers but I never got
>the stock
> radiator working sufficient enough for prolonged full
>power climbs in
> hot weather.
> 3) Use an oil to water heat exchanger. This means that
>you have to focus
> on the air flow of only one radiator, and also don't
>need an oil
> thermostat and still have superfast warm-up times.
> 4) Get away with the entire "dog house". It is ugly and
>it serves no
> purpose.
> 5) Use an adjustable cowl flap to control engine
>temperatures.
> 6) Reroute the exhaust so the cowl opening points to the
>rear. I tried
> to build an exhaust augmentor but I'm not sure if it
>really works. In
> any case, the cowling air escaping around the exhaust
>opening flows in
> the correct direction and doesn't upset the air stream.
>
> So. what I'm using now is a thin radiator, mounted flush
>with the
> underside of the cowling. (Custom made, 300 Euro's). It
>is slanted so it
> follows the shape of the cowling. Because of the angle
>the horizontal
> frontal area is very small, you can say it forms a
>natural diffuser.
>Flow is controlled by an exit cowl flap. If the air flow
>is restricted
> by the cowl flap, the air in front of the radiator even
>doesn't "see"
> the radiator, the air flows over the surface and follows
>the shape of
> the cowling as if the radiator doesn't exist at all.
> The air leaving the radiator is recycled because it
>flows under the
> engine, taking the heat of exhaust and turbo with it on
>its way out. No
> separate openings for these items are necessary.
> The coolant is also used to cool (or heat!) the oil via
>a heat
> exchanger. Apart from the heat-up time, the oil
>temperature is always 5C
> higher than the coolant temperature, which I consider to
>be perfect. I
> keep the water at 105C and the oil at 110C in all
>conditions. This is
> the best for the engine and the efficiency.
>For cylinder cooling you can use the standard Rotax
>shroud with the
> opening under the propeller. I made my own shroud
>because of the vaccuum
> pad alternator which prevents the use of the standard
>shroud, but the
> idea is similar.
>
> After one year of using this, I can state the following
>results:
> 1) Adequate cooling in ALL conditions. I have excecuted
>a full power
> climb from 0ft to FL095 at 80 knots in an inversion
>layer with a OAT of
> 35C for most of the trajectory, with the water temp not
>exceeding 110C
> and the oil not exceeding 120C. This was with the cowl
>flap not yet
> fully open. Although not yet tested, I'm convinced that
>the cooling
> would work ok in OAT's of 45C as well.
> 2) In cruise the cowl flap is typically only half an
>inch open; i.e. it
> protrudes only a half inch below the belly of the
>airplane. Compare that
> with the huge tunnelexit of the stock XS design!
> 3) Unlimited ground operations, even in very hot
>weather.
> 4) Superfast heat-up times. 5 minutes is even in the
>winter sufficient
> to get the oil temp far enough up into the yellow arc to
>perform a take off.
> 5) Low cowling temperatures, despite the lack of
>ventilation.
> Temperatures don't exceed 60C, except briefly after
>engine shut off. In
> hot weather I open the oil tank access door after
>landing for a few
> minutes to let the hot air out.
> 6) Weight savings. I have not weighed the difference,
>but I'm sure the
> flat radiator and heat exchanger is lighter than the two
>stock radiators
> and tunnel hard ware.
>
> About the picture:
> This was the unfinished design. The final version is
>even smoother.
> The only exit opening here is the proptrusion of the
>"tunnel" against
> the belly of the fuselage. The nose wheel opening is
>sealed off and
> flush with the belly. The cowl flap can be extended
>further but this is
> the typical cruise setting. Quite a difference compared
>to the stock
> tunnel, eh?
>
> In addition of the rectangular radiator opening I have
>two round inlets.
> The one on the starboard side serves the intercooler for
>the turbo (via
> a wedge diffuser and butterfly valve). You don't need
>this inlet if you
> don't have an intercooler. The opening on the port side
>connects to the
> cylinder wall shrouds. You could use the standard Rotax
>shroud with the
> opening below the prop instead, but I made a round inlet
>on the port
> side to maintain the symmetry. In most setups you can
>ommit these round
> inlets. That would be an even cleaner nose!
> The starboard inlet also facilitates the engine air
>intake. The port
> inlet also connects to a very small auxilliary oil
>radiator. Without
> this radiator the water-oil delta T was 10C, and with
>the extra radiator
> I got my desired delta T of 5C. It is not really needed
>if you are
> satisfied with the standard delta T.
> On the top of the firewall you see a small servo, a
>similar model as the
> vertical trim servo. This servo connects via a rod to
>the cowl flap. The
> cowl flap hinges close to the radiator so even when it
>is fully open the
> angle is very low. A simple but very efficent mechanism!
>
> The front exhaust elbows are wrapped to save the cowling
>which is very
> close.
>
> If there is enough interest in this subject, I'm willing
>to write an
> article about it. There is a lot of testing, reading,
>thinking, and
> learning from failures behind this design.
> Although I have been flying a year with it now, I have
>only recently
> been able to test it in very hot and demanding
>conditions during our
> just finished round trip in Corsica, Italy and Croatia
>and overflying
> the Alps twice.
>
> More about that trip later.
>
>Frans
>
Message 4
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| Subject: | Re: pitot/static port cover? |
Frans, I don't normally cover mine, having decided the
likelihood and nuisance of leaving it on was greater than
the possibility of something nesting there, but I carry a
roll oh red PVC tape to cover my fuel tank outlets if I
expect heavy rain and I guess that would serve for areas
where funny nesting insects are to be found.
Regards, David Joyce, G-XSDJ
On Wed, 20 Jun 2012 16:44:50 +0200
Frans Veldman <frans@privatepilots.nl> wrote:
><frans@privatepilots.nl>
>
> Hi,
>
> On our recent trip to Croatia we left the aircraft for
>two days on a
> very hot airfield. When we came back to depart we
>discovered that the
> ASI was reading 70 knots... (Luckily our pitot system is
>air tight
> otherwise we would have discovered it during our take
>off run or later).
> Investigation (which is no fun on a very hot tarmac
>without shadow)
> revealed that the pitot tube was internally sealed off
>by some
> substance. Even poking and moving with a piece of wire
>inside the pitot
> it was not possible to get air flow through it, despite
>all the stuff
> that came out. Whatever was in there was even past the
>90 degree bend.
> Some insect had made a whole nest or something inside
>the tube.
> I finally had to take the pitot/static assembly out to
>get it cleaned
> with compressed air.
>
> To avoid this in the future I would like to use a pitot
>cover, but in
> the past I could never find a standard cover that fits,
>so after many
> hours without a cover I thought I could live without
>one. Clearly not.
> So, has anyone found some suitable standard cover or do
>I need to make
> something myself?
>
>Frans
>
>Un/Subscription,
>Forums!
>Admin.
>
>
>
Message 5
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| Subject: | Re: Pitot/static port cover. |
Frans,
Try a suitably sized piece of polythene tubing bent over to cover both pitot
and static tubes and tie a red flag to it. Works great.
Mike
Message 6
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| Subject: | pitot/static port cover? |
Hi Frans,
Many standard covers exist for this, just have a look at any catalog (see
http://www.aircraftspruce.com/menus/fb/covers_pitot.html)
You can also use a mail of the correct diameter to close the pitot but make
sure to attach something very visible to it to a void to forget it before
taking-off.
Max Cointe
F-PMLH TriGear Kit #560
912ULS Airmaster 420 hours
mcointe@free.fr
-----Message d'origine-----
De: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] De la part de Frans Veldman
Envoy: mercredi 20 juin 2012 16:45
: europa-list@matronics.com
Objet: Europa-List: pitot/static port cover?
Hi,
On our recent trip to Croatia we left the aircraft for two days on a
very hot airfield. When we came back to depart we discovered that the
ASI was reading 70 knots... (Luckily our pitot system is air tight
otherwise we would have discovered it during our take off run or later).
Investigation (which is no fun on a very hot tarmac without shadow)
revealed that the pitot tube was internally sealed off by some
substance. Even poking and moving with a piece of wire inside the pitot
it was not possible to get air flow through it, despite all the stuff
that came out. Whatever was in there was even past the 90 degree bend.
Some insect had made a whole nest or something inside the tube.
I finally had to take the pitot/static assembly out to get it cleaned
with compressed air.
To avoid this in the future I would like to use a pitot cover, but in
the past I could never find a standard cover that fits, so after many
hours without a cover I thought I could live without one. Clearly not.
So, has anyone found some suitable standard cover or do I need to make
something myself?
Frans
Message 7
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|
| Subject: | Re: pitot/static port cover? |
Frans,=0A=0ASo, you have those little plug bugs over there too.=0A=0AI use
the "Plane Sights Universal Pitot Tube Cover."=C2-=0A=0AI purchased min
e at a booth at Airventure a couple years ago.=0A=0AThis picture is off of
Amazon.com where you can do a search on "Pitot Tube Covers" to come up wi
th it and a whole host of other options as well.=0ABlue skies & tailwinds,
=0ABob Borger=0AEuropa XS Tri, Rotax 914 w/ Intercooler & Airmaster C/S Pr
op=0ALittle Toot Sport Biplane, Lycoming AEIO-320 EXP=0A3705 Lynchburg Dr.
=0ACorinth, TX 76208-5331=0AH: 940-497-2123=0AC: 817-992-1117=0A=0AOn Jun
20, 2012, at 09:44 AM, Frans Veldman <frans@privatepilots.nl> wrote:=0A=0A
=0AHi,=0A=0AOn our recent trip to Croatia we left the aircraft for two day
s on a=0Avery hot airfield. When we came back to depart we discovered that
the=0AASI was reading 70 knots... (Luckily our pitot system is air tight=0A
otherwise we would have discovered it during our take off run or later).=0A
Investigation (which is no fun on a very hot tarmac without shadow)=0Areve
aled that the pitot tube was internally sealed off by some=0Asubstance. Ev
en poking and moving with a piece of wire inside the pitot=0Ait was not po
ssible to get air flow through it, despite all the stuff=0Athat came out.
Whatever was in there was even past the 90 degree bend.=0ASome insect had
made a whole nest or something inside the tube.=0AI finally had to take th
e pitot/static assembly out to get it cleaned=0Awith compressed air.=0A=0A
To avoid this in the future I would like to use a pitot cover, but in=0Ath
e past I could never find a standard cover that fits, so after many=0Ahour
s without a cover I thought I could live without one. Clearly not.=0ASo, h
as anyone found some suitable standard cover or do I need to make=0Asometh
ing myself?=0A=0AFrans=0A
Message 8
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| Subject: | Re: Contact detail & Help |
Ha ha.... I wondered who was going to be first out of the closet, me or
Fran=92s. Fran=92s and I have been collaborating on a journey of discovery
for
the last couple of years.
I have been reluctant to share what I have been doing, mostly because up
until now I have only been able to tell everyone what doesn't work! Both
Fran's and I can share funny stories of tuft test showing air flow out
where it should be flowing in, some take offs where we couldn't get back on
the ground quick enough due overheating and lots of work and re work.
For me, I am still works in progress, but over the next winter I plan on a
fourth iteration over next winter which will be a similar design to Fran=92
s.
If I can persuade my friend Graham Singleton to come and visit, it might
even a new carbon fiber cowling :)
At a high level the sources of design material we used were:
- Kays & London wedge diffuser
- Kuchemann & Weber trumpet diffuser
- Cooling design notes from the Central States Canard Group
- Taper diffuser design from the Canard group
- Oil Streaking presentations from the Central States Canard
Group
- Think Vs. think radiator notes from Rotary Engine forums.
- Cooling Vs flow data from Rotax and Laminova
Our design criteria was:
Cooling that works in all phases of operation:
- Ground
- Climb
- Cruise
Operates over a range of -5c to 40c
Offers the lowest drag possible
This ultimately dictated a few design solutions:
*
*
*Cowl Flap. *
This is the only way we could get cooling over a large speed range and
ambient temperature.
*Laminova liquid oil heat exchanger.*
In one of the design iterations that Fran's had created he had the oil and
water radiators separated. Although this provided plenty of oil and liquid
cooling it caused a long cycle time to bring the oil temperature up to
operating temperature. The Laminova solves this problem. One problem that
Fran's and I have not been able to solve is the need for a small axillary
oil radiator.
*Thick Vs. Thin Radiators.*
I was ultimately able to make the thick radiator work with a Kuchemann &
Weber trumpet diffuser, but I intend to abandon this. From our research we
have discovered that 70 to 80% of the heat exchange occurs in the first
20mm of the radiator.
*Diffused Inlets.*
At first glance Fran's cowl appears to have no diffuser on the inlet side
of the radiator, however it works very well. After reading the design
notes for the Kays & London wedge diffuser our hypothesis is that because
the coolant radiator is at an angle to the relative wind it behaves like a
wedge diffusers.
*Other thoughts & observations.*
Fran=92s has been flying a working solution for nearly a year and his desig
n
can be used as is. I am doing some experimentation with a single diffused
inlet that provides the engine combustion air, inter cooler and the engine
shroud. Given the level of effort this has proved to be I wouldn=92t
recommend anyone copying what I have done, and it remains to be seen if it
even works.
Over next winter I plan on removing the thick radiator and I expect that
this will be a lower drag configuration over what I have.
Pointing the exhaust back is offers a lot of drag reduction. I have some
photographs that show the exhaust plume on the old style exhaust shooting
out nearly 2 meters. For monowheel the exhaust needs to be much longer so
that carbon monoxide does not find its way into cabin via the tunnel.
Unfortunately this was complex bit of stainless steel to fabricate.
When my cowling is fully open it is the same angle as the standard
cowling. I see 8 knots difference between fully open and fully closed.
This isn't an exact comparison because when my cowl flap is open air will
spill around the side and I expect this would be higher drag than the
original cowl. I have done a number of long cross country trips and for
the same manifold pressure settings I am seeing about 5 knots increase in
my cruise. I have Warp drive blades and I do not wing root fairings so my
set up is not as efficient as Fran=92s.
Regards, Paul
Message 9
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| Subject: | bonding fuselage top |
Hi guys, Paul Munford here, kit 625 tri gear NG. I'm soon to bond the
fuselage top & was wondering just how much resin to mix ??? Anyone out
there done this job recently ? Also any tips on mixing large amounts of
resin & flox for this job. Thanx in advance.
Message 10
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| Subject: | Re: bonding fuselage top |
Paul, What you really need is an extra pair of educated
hands (I.e. another builder) it is more a question of
getting it all spread on all the mating surfaces before it
begins to go off. Making a bit extra if needs be would be
a minor part of it. Do you have another builder living
nearby who could come and help? I assume you have got it
all lined up with cllecoes to hold it in position and that
you will cover the clecoes with grease to help get them
out when the resin is set but not brittle.
Regards, David Joyce, G-XSDJ
On Wed, 20 Jun 2012 18:11:13 +0100
"Paul & Vanessa Munford" <pmdental@btinternet.com>
wrote:
> Hi guys, Paul Munford here, kit 625 tri gear NG. I'm
>soon to bond the fuselage top & was wondering just how
>much resin to mix ??? Anyone out there done this job
>recently ? Also any tips on mixing large amounts of resin
>& flox for this job. Thanx in advance.
Message 11
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| Subject: | bonding fuselage top |
Hi Paul
Just a suggestion, if you don't want to risk gluing up your clecoes, small
self tapping screws work just as well. Pop them in a paper cup and give
them a good spray of WD40 before use.
Pete
PS David is quite correct it is a 2 man (sorry person!) job.
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of David Joyce
Sent: 20 June 2012 18:53
Subject: Re: Europa-List: bonding fuselage top
Paul, What you really need is an extra pair of educated
hands (I.e. another builder) it is more a question of
getting it all spread on all the mating surfaces before it
begins to go off. Making a bit extra if needs be would be
a minor part of it. Do you have another builder living
nearby who could come and help? I assume you have got it
all lined up with cllecoes to hold it in position and that
you will cover the clecoes with grease to help get them
out when the resin is set but not brittle.
Regards, David Joyce, G-XSDJ
On Wed, 20 Jun 2012 18:11:13 +0100
"Paul & Vanessa Munford" <pmdental@btinternet.com>
wrote:
> Hi guys, Paul Munford here, kit 625 tri gear NG. I'm
>soon to bond the fuselage top & was wondering just how
>much resin to mix ??? Anyone out there done this job
>recently ? Also any tips on mixing large amounts of resin
>& flox for this job. Thanx in advance.
--
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.
Message 12
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| Subject: | Re: pitot/static port cover? |
I used about 8 inches of clear tubing that is sized to slip over the pitot/static,
folded in half to go over both. At the fold a nice visible red ribbon held
with a zip tie. Same sort of thing on the fuel vent.
Kevin
On Jun 20, 2012, at 7:44 AM, Frans Veldman <frans@privatepilots.nl> wrote:
>
> Hi,
>
> On our recent trip to Croatia we left the aircraft for two days on a
> very hot airfield. When we came back to depart we discovered that the
> ASI was reading 70 knots... (Luckily our pitot system is air tight
> otherwise we would have discovered it during our take off run or later).
> Investigation (which is no fun on a very hot tarmac without shadow)
> revealed that the pitot tube was internally sealed off by some
> substance. Even poking and moving with a piece of wire inside the pitot
> it was not possible to get air flow through it, despite all the stuff
> that came out. Whatever was in there was even past the 90 degree bend.
> Some insect had made a whole nest or something inside the tube.
> I finally had to take the pitot/static assembly out to get it cleaned
> with compressed air.
>
> To avoid this in the future I would like to use a pitot cover, but in
> the past I could never find a standard cover that fits, so after many
> hours without a cover I thought I could live without one. Clearly not.
> So, has anyone found some suitable standard cover or do I need to make
> something myself?
>
> Frans
>
>
>
>
Message 13
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| Subject: | bonding fuselage top |
Unless you live somewhere cold, I would suggest mixing it in batches or get
a few helpers, from memory I used about 400 gm for the whole
Thing (that's mixed weight) in two batches, one for each side. That way you
have plenty of time to apply it without worrying it will exotherm
In the mixing container
Regards
craig
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Paul & Vanessa
Munford
Sent: Thursday, June 21, 2012 3:11 AM
Subject: Europa-List: bonding fuselage top
Hi guys, Paul Munford here, kit 625 tri gear NG. I'm soon to bond the
fuselage top & was wondering just how much resin to mix ??? Anyone out there
done this job recently ? Also any tips on mixing large amounts of resin &
flox for this job. Thanx in advance.
No virus found in this message.
Checked by AVG - www.avg.com
Message 14
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| Subject: | Re: DOTH Haverford West mid-day or maybe Aberporth |
Visit report:
https://www.facebook.com/media/set/?set=a.10151488992365715.482751.754055714&type=1&l=a8ec12e71d
First 4 hour trip, landed at Haverford west. Need to solve fuel smell and also
get a small coolant leak on cool down.
Had to skirt round Aberporth due to some pesky UAV supposedly flying - hope this
is not a sign of things to come.
--------
Graeme Bird
G-UMPY
Mono Classic/XS FWFD 912ULS/Warp drive FP
Newby: 35 hours
g(at)gdbmk.co.uk
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=376159#376159
Message 15
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| Subject: | Re: DOTH Haverford West mid-day or maybe Aberporth |
Hi! Graeme
Sorry I couldn't make your doth ...just too much on at present but I know
the Haverford west air field and beautiful coast line. Well done with the
4 hour flight ! Last year I did one 4 hours 30 mins to Krems from Texel to
the Austrian Rally. Thought I'd have a problem with pee time but cramp got
me first ! then no where to put down since all the vinyards had wire
stretched over them !
Since then I have a pee tube fitted so can get satisfaction of peeing all
over certain areas I pass over !
Regards
Bob H G-PTAG
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of graeme bird
Sent: 20 June 2012 21:30
Subject: Europa-List: Re: DOTH Haverford West mid-day or maybe Aberporth
Visit report:
https://www.facebook.com/media/set/?set=a.10151488992365715.482751.754055714
&type=1&l=a8ec12e71d
First 4 hour trip, landed at Haverford west. Need to solve fuel smell and
also get a small coolant leak on cool down.
Had to skirt round Aberporth due to some pesky UAV supposedly flying - hope
this is not a sign of things to come.
--------
Graeme Bird
G-UMPY
Mono Classic/XS FWFD 912ULS/Warp drive FP
Newby: 35 hours
g(at)gdbmk.co.uk
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=376159#376159
Message 16
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| Subject: | bonding fuselage top |
Hi! Paul
Can't remember the amounts but if you use Redux then there's no panic re
time! And you can mix more as you go ! Don't forget the light behind the
joint to show where there's no contact for bond.
The self tapper screws is a good tip.
Regards
Bob H arrison G-PTAG .....been there done that !!!!
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Paul & Vanessa
Munford
Sent: 20 June 2012 18:11
Subject: Europa-List: bonding fuselage top
Hi guys, Paul Munford here, kit 625 tri gear NG. I'm soon to bond the
fuselage top & was wondering just how much resin to mix ??? Anyone out there
done this job recently ? Also any tips on mixing large amounts of resin &
flox for this job. Thanx in advance.
Message 17
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| Subject: | pitot/static port cover? |
Hi all
I owned a 1948 Cessna 170 for 19 years. I had a Mud Dabber fill my Pitot
once for a bit of excitement even though I had the number two cover on
the ACS link that supposedly stays closed until 40 MPH. I was perplexed
at how this happened? A few days later at some far off airstrip, it was
howling out. I observed the fool pitot cover open, to my amazement i saw
a Mud dabber somehow navigate it's way to the opened tube and climb
in! That was at about 10 year point. I used a push over the tube
with red flag and never had a problem again.
Ron Parigoris
<mcointe@free.fr>
>
> Hi Frans,
>
> Many standard covers exist for this, just have a look at any catalog
(see
> http://www.aircraftspruce.com/menus/fb/covers_pitot.html)
> You can also use a mail of the correct diameter to close the pitot
but
> make
> sure to attach something very visible to it to a void to forget it
before
> taking-off.
>
> Max Cointe
> F-PMLH TriGear Kit #560
> 912ULS Airmaster 420 hours
> mcointe@free.fr
>
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