Today's Message Index:
----------------------
1. 01:07 AM - Re: 1.5 degrees right? (spcialeffects)
2. 02:41 AM - Re: Fuel Cover Belt (Raimo Toivio)
3. 03:39 AM - Re: 1.5 degrees =?UTF-8?Q?right=3F? (davidjoyce@doctors.org.uk)
4. 03:52 AM - Re: 1.5 degrees right? (Roger Sheridan)
5. 06:46 AM - EUROPA XS GAS STRUTS (willydewey)
6. 09:40 AM - Re: Re: Fuel Cover Belt (Tim Ward)
7. 11:19 AM - Re: Re: Fuel Cover Belt (Raimo Toivio)
8. 01:58 PM - Rubber too hard or too soft? (William Bliss)
9. 02:09 PM - Re: 1.5 degrees right? (nigel_graham@m-tecque.co.uk)
10. 03:03 PM - Re: 1.5 degrees right? (jonathanmilbank)
11. 03:07 PM - Re: 1.5 degrees right? (Robert Borger)
Message 1
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Subject: | Re: 1.5 degrees right? |
Hello Jonathan, Frank Xuereb here. If you watch 'a plane is born' when he gets
the engine delivered Mark gives quite a good explanation as to the reason for
the offset. Basically on full throttle the wind wash created by the prop would
hit the port side of the fin and give a tendency to push you to the left. This
is of course easily corrected by right rudder input but to help reduce this
effect the back of the engine is offset by 27mm but keeps the prop flange at 90
degrees.
Good luck, Frank kit 165
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=465092#465092
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Subject: | Re: Fuel Cover Belt |
Hi Tim,
I had already forgotten I sent you this belt.
Must be about 7 years ago?
Very nice to see you have found a way to use it!
I also noticed the blue color match well to your blue cobra!
I have used these belts to secure all kind of stuff like beer boxes.
Also, its handy when securing a dog or a cats cage.
allekirjoitus
I elected to attach the fuel cobra by Velcro (lighter way but absolutely
not so sexy ;).
This winter I will finally prepare a revolutionary safety belt mod.
Coming back.
Tim, I just happen to look the satellite image from your home.
You have a very homelike home and a nice pool there.
I noticed also something very exciting - giant letters TIM on the roof!
I hereby request a permission to copy that idea!
(I have OH-XRT letters on the roof of the EFTP hangar, but never
understood they could be also here, home)
Thanks!
Cheers,
Raimo
Europa OH-XRT #417
Finland
<mailto:info@rwm.fi>
14.1.2017, 23:51, Tim Ward kirjoitti:
> Hi Raimo,
> Just read your article on shifting your Europa and thought I must show Raimo
the use of his seat belt he sent me.
> As my fuel cover kept on falling off and trying different ways to keep it in
place I finally came across the perfect way. The belt goes right around the 'cobra'
which makes it a reliable fix.
> Many thanks, looks perfect. Will turn it up the other way.
> Cheers,
> Tim
>
>
> Tim Ward
> 12 Waiwetu Street,
> Fendalton,
> Christchurch, 8052
> New Zealand
>
> ward.t@xtra.co.nz
>
> Mob +64 210640221
>
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Subject: | Re: 1.5 degrees =?UTF-8?Q?right=3F? |
Jonathan, I suspect you are dealing with two distinct effects here. The
tendency to roll to the right suggests to me that you have slightly
different effective angles of attack on the two wings, either because of
how the wings were constructed or because of how they were attached to
the fuselage. This seems to be very common and a small piece of
triangular section wood, length adjusted for effect, under (in your case
) the port aileron will correct it. As previously stated the engine
offset is there to correct the tendency for the clockwise spiral
propwash around the fuselage impinging on the left side of the fin and
tending to produce a left turn. This effect is most noticeable on take
off (and probably also in monos) when at max power and lowish speed with
limited rudder authority, when a significant amount of Right rudder is
needed to keep in a straight line. It is also noticeable in a full power
lowish speed climb. I believe that the amount of offset is designed to
allow hands off balanced straight flight at typical cruise speeds/power,
whilst also helping to maintain control authority on take off. Regards,
David Joyce,GXSDJ
On 2017-01-14 22:41, jonathanmilbank wrote:
>
> I'm converting my Classic to XS firewall forward and the instructions for mounting
the engine call for the 4 washers on each lord mount to be arranged so that
the engine is angled 1.5 degrees to the right.
>
> The Classic build manual didn't give this stipulation and so mine was pointing
straight ahead. What effect will there likely be when I start flying in the
new configuration. Up until now there has been a tendency for the aircraft to
roll gently to the right in the cruise.
>
> Will angling the engine to the right make the right roll tendency better or worse?
Please give me the aerodynamic logic for this 1.5 degree offset.
>
> Thanks.
> Jonathan
> Of how they are mounted on the fuselage. This is very common and can be readily
corrected with a small trangular section of wood stuck under the (in your case)
port aileron
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=465078#465078 [1]
>
Links:
------
[1] http://forums.matronics.com/viewtopic.php?p=465078#465078
[2] http://www.matronics.com/Navigator?Europa-List
[3] http://forums.matronics.com
[4] http://wiki.matronics.com
[5] http://www.matronics.com/contribution
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Subject: | Re: 1.5 degrees right? |
Further info here for bookworms!
https://dl.dropboxusercontent.com/u/246742/TailWheel1.pdf
> On 15 Jan 2017, at 11:38, davidjoyce@doctors.org.uk wrote:
>
> Jonathan, I suspect you are dealing with two distinct effects here.
The tendency to roll to the right suggests to me that you have slightly
different effective angles of attack on the two wings, either because of
how the wings were constructed or because of how they were attached to
the fuselage. This seems to be very common and a small piece of
triangular section wood, length adjusted for effect, under (in your case
) the port aileron will correct it. As previously stated the engine
offset is there to correct the tendency for the clockwise spiral
propwash around the fuselage impinging on the left side of the fin and
tending to produce a left turn. This effect is most noticeable on take
off (and probably also in monos) when at max power and lowish speed with
limited rudder authority, when a significant amount of Right rudder is
needed to keep in a straight line. It is also noticeable in a full power
lowish speed climb. I believe that the amount of offset is designed to
allow hands off balanced straight flight at typical cruise speeds/power,
whilst also helping to maintain control authority on take off. Regards,
David Joyce,GXSDJ
>
>
>
> On 2017-01-14 22:41, jonathanmilbank wrote:
>
<jdmilbank@yahoo.co.uk <mailto:jdmilbank@yahoo.co.uk>>
>>
>> I'm converting my Classic to XS firewall forward and the instructions
for mounting the engine call for the 4 washers on each lord mount to be
arranged so that the engine is angled 1.5 degrees to the right.
>>
>> The Classic build manual didn't give this stipulation and so mine was
pointing straight ahead. What effect will there likely be when I start
flying in the new configuration. Up until now there has been a tendency
for the aircraft to roll gently to the right in the cruise.
>>
>> Will angling the engine to the right make the right roll tendency
better or worse? Please give me the aerodynamic logic for this 1.5
degree offset.
>>
>> Thanks.
>> Jonathan
>> Of how they are mounted on the fuselage. This is very common and can
be readily corrected with a small trangular section of wood stuck under
the (in your case) port aileron
>>
>>
>>
>> Read this topic online here:
>>
>> http://forums.matronics.com/viewtopic.php?p=465078#465078
<http://forums.matronics.com/viewtopic.php?p=465078#465078>
>>
>>
>>
>>
>>
>>
>> ttp://www.matronics.com/Navigator?Europa-List
>> ics.com
>> .com
>> .matronics.com/contribution
>>
>>
>>
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Subject: | EUROPA XS GAS STRUTS |
Hi Guys
My Gas struts are becoming a little feeble and probably need regassing.
When I had a CT2K I did this myself by placing them inside my compressor storage
tank. It was a bit hit and miss but worked quite well.
As I have a bit more time I would like to repeat the exercise but would appreciate
from a member the exact pressure the XS struts should be
Thanks in anticipation and Blue Skies and Light Winds for 2017
Bill Dewey Guildford U.K.
--------
Give a wise man knowledge and he will be yet wiser
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=465099#465099
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Subject: | Re: Fuel Cover Belt |
Hi Raimo,
Permission granted!
Every time I take the children flying, when they were young, they would alw
ays ask "which house is ours". Remedy, when painting the roof which has a fl
at area, paint a big 'TIM' in bold white. Now we have no problems even with o
ther passengers it is easy.
Hot here now in the 30s Celsius so a pool is ideal. We sometimes get snow in
the winter, now it is less often due to climate warming.
Going flying today up the Kaikoura coast to see the earthquake damage and th
en to Omaka airfield to see Peter Jackson's World War 2 fighter plane museum
. Meet my oldest son Angus who will fly down from Palmerston North where he i
s flying instructing with Massey University Aviation College.
All the best,
Keep warm,
Cheers,
Tim
Tim Ward
12 Waiwetu Street,
Fendalton,
Christchurch, 8052
New Zealand
ward.t@xtra.co.nz
Mob +64 210640221
> On 15/01/2017, at 11:36 PM, Raimo Toivio <raimo.toivio@rwm.fi> wrote:
>
> Hi Tim,
>
> I had already forgotten I sent you this belt.
> Must be about 7 years ago?
>
> Very nice to see you have found a way to use it!
> I also noticed the blue color match well to your blue cobra!
>
> I have used these belts to secure all kind of stuff like beer boxes.
> Also, it=C2=B4s handy when securing a dog or a cat=C2=B4s cage.
>
> <Europa_extra_seat_belt_2017 (Mobile).jpg>
>
> I elected to attach the fuel cobra by Velcro (lighter way but absolutely n
ot so sexy ;).
>
> This winter I will finally prepare a revolutionary safety belt mod.
> Coming back.
>
> Tim, I just happen to look the satellite image from your home.
> You have a very homelike home and a nice pool there.
> I noticed also something very exciting - giant letters TIM on the roof!
>
> I hereby request a permission to copy that idea!
>
> (I have OH-XRT letters on the roof of the EFTP hangar, but never understoo
d they could be also here, home)
>
> Thanks!
>
>
> Cheers,
> Raimo
> Europa OH-XRT #417
> Finland
>
>
> 14.1.2017, 23:51, Tim Ward kirjoitti:
>> Hi Raimo,
>> Just read your article on shifting your Europa and thought I must show R
aimo the use of his seat belt he sent me.
>> As my fuel cover kept on falling off and trying different ways to keep it
in place I finally came across the perfect way. The belt goes right around t
he 'cobra' which makes it a reliable fix.
>> Many thanks, looks perfect. Will turn it up the other way.
>> Cheers,
>> Tim
>>
>>
>>
>>
>>
>> Tim Ward
>> 12 Waiwetu Street,
>> Fendalton,
>> Christchurch, 8052
>> New Zealand
>>
>> ward.t@xtra.co.nz
>>
>> Mob +64 210640221
>>
>
Message 7
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Subject: | Re: Fuel Cover Belt |
Hi Tim,
thanks for that - obviously I have to make not-white and illuminated
letters XRT to make them visible.
Here is 2 years old satellite image from our place - Koivuniementie *69*
Lempl Finland. Apron and twr
has been built afterwards. Europa Factory is the uppermost building. You
can see our pool under the word "tie" [road].
The pool is covered to make it cleaner and more economical. During blue
sky days,
the covers are sliding away. We heat it by water-air heat pump to keep
it continously +32C.
Max power is 20kW. When it goes below +30C, we let it freeze. That means
its
usable from Mars-April to November-December. You see the sign behind?
And red light?
Im pretty sure you like this!
And also this.
We need it to remember, that there is a beer tap inside. During spring,
we install one beer barrell there. When its empty, we connect the tap
to the fresh water (wifes order!).
This is a typical summer-temperature-set up here:
Pool (Lagoon, green) +32C
Pool area when coverred (Caribbean, orange) +21C (max +48C!!!)
Air (Finland, white) +14C (max below +30C in shadow)
River (Lake, blue) +15C (max below +26C)
***
About climate change, I heard today that there will be jackals in
Finland soon.
Maybe kangaroos and one day Kiwi-birds also as well as opossums.
Massey University Aviation College sounds fantastic!
I have to give a tip to my older daughter...
Yes, all the best and earthquakeless time for you.
Keep cold!
Cheers,
Raimo
Finland
PS: this was not so Europa-related posting. However, its because
Europas. Sorry...
And yes, you all can order FB beer from us!
- only beer in the world brewed to aircraft standards by pilots to
pilots and also to normal people...
<mailto:info@rwm.fi>
15.1.2017, 19:39, Tim Ward kirjoitti:
> Hi Raimo,
> Permission granted!
> Every time I take the children flying, when they were young, they
> would always ask "which house is ours". Remedy, when painting the roof
> which has a flat area, paint a big 'TIM' in bold white. Now we have no
> problems even with other passengers it is easy.
> Hot here now in the 30s Celsius so a pool is ideal. We sometimes get
> snow in the winter, now it is less often due to climate warming.
> Going flying today up the Kaikoura coast to see the earthquake damage
> and then to Omaka airfield to see Peter Jackson's World War 2 fighter
> plane museum. Meet my oldest son Angus who will fly down from
> Palmerston North where he is flying instructing with Massey University
> Aviation College.
>
> All the best,
>
> Keep warm,
>
> Cheers,
> Tim
>
>
> Tim Ward
> 12 Waiwetu Street,
> Fendalton,
> Christchurch, 8052
> New Zealand
>
> ward.t@xtra.co.nz <mailto:ward.t@xtra.co.nz>
>
> Mob +64 210640221
>
>
> On 15/01/2017, at 11:36 PM, Raimo Toivio <raimo.toivio@rwm.fi
> <mailto:raimo.toivio@rwm.fi>> wrote:
>
>> Hi Tim,
>>
>> I had already forgotten I sent you this belt.
>> Must be about 7 years ago?
>>
>> Very nice to see you have found a way to use it!
>> I also noticed the blue color match well to your blue cobra!
>>
>> I have used these belts to secure all kind of stuff like beer boxes.
>> Also, its handy when securing a dog or a cats cage.
>> allekirjoitus
>> <Europa_extra_seat_belt_2017 (Mobile).jpg>
>>
>> I elected to attach the fuel cobra by Velcro (lighter way but
>> absolutely not so sexy ;).
>>
>> This winter I will finally prepare a revolutionary safety belt mod.
>> Coming back.
>>
>> Tim, I just happen to look the satellite image from your home.
>> You have a very homelike home and a nice pool there.
>> I noticed also something very exciting - giant letters TIM on the roof!
>>
>> I hereby request a permission to copy that idea!
>>
>> (I have OH-XRT letters on the roof of the EFTP hangar, but never
>> understood they could be also here, home)
>>
>> Thanks!
>>
>>
>> Cheers,
>> Raimo
>> Europa OH-XRT #417
>> Finland
>>
>>
>> <mailto:info@rwm.fi>
>> 14.1.2017, 23:51, Tim Ward kirjoitti:
>>> Hi Raimo,
>>> Just read your article on shifting your Europa and thought I must show Raimo
the use of his seat belt he sent me.
>>> As my fuel cover kept on falling off and trying different ways to keep it in
place I finally came across the perfect way. The belt goes right around the
'cobra' which makes it a reliable fix.
>>> Many thanks, looks perfect. Will turn it up the other way.
>>> Cheers,
>>> Tim
>>>
>>>
>>>
>>>
>>> Tim Ward
>>> 12 Waiwetu Street,
>>> Fendalton,
>>> Christchurch, 8052
>>> New Zealand
>>>
>>> ward.t@xtra.co.nz
>>>
>>> Mob +64 210640221
>>>
>>
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Subject: | Rubber too hard or too soft? |
Dear All
I have lost the thread - with the important details about the engine
mount rubbers. Are the ones Europa have supplied said to be too hard or
too soft? Does anyone know where the correct ones can be bought?
William G-WUFF
Message 9
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Subject: | Re: 1.5 degrees right? |
Jonathan,
I think you have provided the answer to your own question.
The fact that you have run your Classic with no engine offset and
noticed no asymmetric flying characteristics speaks volumes.
The whole idea of canting an engine sideways and forcing the propeller
disc through the air at anything other than normal to the oncoming
airstream is daft.
The theory that canting the engine sideways will counter the yaw
effect of the prop wash seems to be based on a misunderstanding of
what is really happening and its done because thats how its always
been done!
On your Classic, you sensibly mounted your engine head on to the wind
and you set you propeller blades pitch to the recommended angle. Each
time the blades rotate their angles of attack remain equal to each
other and constant to the oncoming wind and each blade generates the
same thrust throughout each revolution of the prop.
Now consider what happens when you follow the XS build instructions
and cant the engine 1.5 degrees to the right.
If youre flying straight-and-level behind a right-hand tractor (Rotax
912, 914), each time a blade passes over the top of the ark, its pitch
is effectively reduced by 1.5 degrees and as it swings through the
bottom of the ark, its effective pitch is increased by 1.5 degrees.
This means that your propeller is producing significantly more thrust
from the bottom half of the propeller disc than the top half and
that produces a pitch up change in attitude and not the sideways
thrust you had hoped to achieve by mounting the engine sideways.
So if thats true, why has nobody noticed this pitch up attitude?
a good question (even though I asked it myself).
All Europas are fitted with a pitch trimmer so these effects are
unconsciously trimmed out by the pilot during different phases of
flight.
Ah, but what about the propensity to swing to the left on take-off?
- Same thing, different plane.
The Monowheel sits on the ground at a deck angle of (is it about 12
degrees? I forget) so the engine is now canted up at the front by this
amount. At the beginning of the take-off run, the upcoming blade on
the left hand side has 12 degrees wound off its effective pitch, while
the down going blade on the right has 12 degrees added to its pitch.
This produces significantly more thrust on the right hand side of the
disc than the left, resulting in a turning moment to the left. It's a
potential problem with all tail-draggers
The Tri-Gear variant of course sits horizontally on the ground, so has
none of this asymmetric thrust so is less prone to dive off to the
left on take off; another reason why the Tri-Gear is perceived to be
more benign than the Mono.
Canting an engine is a very crude way of addressing a relatively
transient problem Fitting a rudder trimmer would be a far more
elegant solution should it be necessary.
Hope that wasnt too long winded!
Nigel
PS the roll issue has nothing to do with engine position.
Quoting jonathanmilbank <jdmilbank@yahoo.co.uk>:
>
> I'm converting my Classic to XS firewall forward and the
> instructions for mounting the engine call for the 4 washers on each
> lord mount to be arranged so that the engine is angled 1.5 degrees
> to the right.
>
> The Classic build manual didn't give this stipulation and so mine
> was pointing straight ahead. What effect will there likely be when I
> start flying in the new configuration. Up until now there has been a
> tendency for the aircraft to roll gently to the right in the cruise.
>
> Will angling the engine to the right make the right roll tendency
> better or worse? Please give me the aerodynamic logic for this 1.5
> degree offset.
>
> Thanks.
> Jonathan
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=465078#465078
>
>
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Subject: | Re: 1.5 degrees right? |
Wow and what a plethora of replies! Thanks very much to all of you.
Shortly after I posted this topic and before any replies came in, a fellow Europa
pilot confirmed in advance much of what you guys have explained and your responses
are excellent.
He mentioned that when he let someone else have a go on the Europa's controls,
the guy was caught out by the amount of left yaw during the go-around at low speed
from a missed approach. My friend had to assist, so clearly some people would
benefit from the engine being offset by 1.5 degrees.
I suppose that once anyone gets used to the aircraft, then applying right pedal
when increasing power becomes instinctive.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=465122#465122
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Subject: | Re: 1.5 degrees right? |
Nigel,
Thanks for the detailed description. I have often wondered about the
effectiveness of the offset. It just didn=99t seem right to me.
At some point in the future I=99ll have to unbolt the engine for
something. When I do, I=99ll remove the offset and see what
difference it makes.
Blue skies & tailwinds,
Bob Borger
Europa XS Tri, Rotax 914, Airmaster C/S Prop (75 hrs).
Little Toot Sport Biplane, Lycoming Thunderbolt AEIO-320 EXP
3705 Lynchburg Dr.
Corinth, TX 76208-5331
Cel: 817-992-1117
rlborger@mac.com <mailto:rlborger@mac.com>
On Jan 15, 2017, at 4:08 PM, nigel_graham@m-tecque.co.uk wrote:
Jonathan,
I think you have provided the answer to your own question.
The fact that you have run your Classic with no engine offset and
noticed no asymmetric flying characteristics speaks volumes.
The whole idea of canting an engine sideways and forcing the propeller
disc through the air at anything other than normal to the oncoming
airstream is daft.
The theory that canting the engine sideways will counter the yaw effect
of the prop wash seems to be based on a misunderstanding of what is
really happening and it=99s done because =9Cthat=99s
how it=99s always been done=9D!
On your Classic, you sensibly mounted your engine head on to the wind
and you set you propeller blades pitch to the recommended angle. Each
time the blades rotate their angles of attack remain equal to each other
and constant to the oncoming wind and each blade generates the same
thrust throughout each revolution of the prop.
Now consider what happens when you follow the XS build instructions and
cant the engine 1.5 degrees to the right.
If you=99re flying straight-and-level behind a right-hand tractor
(Rotax 912, 914), each time a blade passes over the top of the ark, its
pitch is effectively reduced by 1.5 degrees and as it swings through the
bottom of the ark, its effective pitch is increased by 1.5 degrees.
This means that your propeller is producing significantly more thrust
from the bottom half of the propeller disc than the top half =93
and that produces a pitch up change in attitude =93 and not the
sideways thrust you had hoped to achieve by mounting the engine
sideways.
=9CSo if that=99s true, why has nobody noticed this pitch up
attitude?=9D =93 a good question (even though I asked it
myself).
All Europa=99s are fitted with a pitch trimmer =93 so these
effects are unconsciously trimmed out by the pilot during different
phases of flight.
=9CAh, but what about the propensity to swing to the left on
take-off?=9D - Same thing, different plane.
The Monowheel sits on the ground at a deck angle of (is it about 12
degrees? I forget) so the engine is now canted up at the front by this
amount. At the beginning of the take-off run, the upcoming blade on the
left hand side has 12 degrees wound off its effective pitch, while the
down going blade on the right has 12 degrees added to its pitch. This
produces significantly more thrust on the right hand side of the disc
than the left, resulting in a turning moment to the left. It's a
potential problem with all tail-draggers
The Tri-Gear variant of course sits horizontally on the ground, so has
none of this asymmetric thrust =93 so is less prone to dive off to
the left on take off; another reason why the Tri-Gear is perceived to be
more benign than the Mono.
Canting an engine is a very crude way of addressing a relatively
transient problem =93 Fitting a rudder trimmer would be a far more
elegant solution =93 should it be necessary.
Hope that wasn=99t too long winded!
Nigel
PS the roll issue has nothing to do with engine position.
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