Author: Tom Coombs <n128ec@...> Time: Sun Nov 20, 2005 3:30 pm PST Link
Hi folks:
I was tooling around looking at the pitot tube plumbing and fittings.
I have always been a little suspect of the VANS design pitot, thinking it
may be a little flimsy and perhaps also a little ugly in practice. For
grins, I fabbed and bent the tube for the Vans design and and actually, it's
pretty sturdy, it is however a little ugly. My other concern is with the
placement of this tube, with the plans calling for a hole to be drilled in
the spar.
I do have on hand a AN-5814 Compatible 24v heated head and mount bracket,
but I don't have the extension that would push it 6" from the wing and also
a $10 special from Aircraft Spruce, which has two tubes, one clased off to
act as a static.
Now for the question. Has anyone moved the location of the pitot. I want
to move mine inboard 1 bay from the plan position. Also, my intention is to
move it back about an inch on to the wing skin and support it with a doubler
in that area, anyone done anything similar?
On the other hand, if I were to use the 5814, is the extension absolutely
necessary for this wing section? The amateur aerodynamicist in me says
that it probably is for accuracy...
Thanks.
TC.
--
RV-7 N-128EC (Reserved)
Left Wing.
Airplane Cam: https://coombsonline.hopto.org/cam1
Tom Coombs
tom@...
Author: "gsuit45" <gsuit@...> Time: Mon Nov 21, 2005 7:40 am PST Link
Tom,
I'm going through the same decision as you. Take a look at the Gretz Aero heated pitot
tube mounting kit. It sells for $118, and is specifically designed for RV's, and works with
most pitot tubes. It places the pitot aft of the spar, but in the same bay as the aileron
pushtube. You do need the extension, as you want to keep the pitot extended into the
boundary layer of airflow around the wing.
The gretz website is: www.gretzaero.com
Clayton
RV-7
Beaumont, TX
--- In RV7and7A@yahoogroups.com, Tom Coombs <n128ec@c...> wrote:
>
> Hi folks:
>
> I was tooling around looking at the pitot tube plumbing and fittings.
>
> I have always been a little suspect of the VANS design pitot, thinking it
> may be a little flimsy and perhaps also a little ugly in practice. For
> grins, I fabbed and bent the tube for the Vans design and and actually, it's
> pretty sturdy, it is however a little ugly. My other concern is with the
> placement of this tube, with the plans calling for a hole to be drilled in
> the spar.
>
> I do have on hand a AN-5814 Compatible 24v heated head and mount bracket,
> but I don't have the extension that would push it 6" from the wing and also
> a $10 special from Aircraft Spruce, which has two tubes, one clased off to
> act as a static.
>
> Now for the question. Has anyone moved the location of the pitot. I want
> to move mine inboard 1 bay from the plan position. Also, my intention is to
> move it back about an inch on to the wing skin and support it with a doubler
> in that area, anyone done anything similar?
>
> On the other hand, if I were to use the 5814, is the extension absolutely
> necessary for this wing section? The amateur aerodynamicist in me says
> that it probably is for accuracy...
>
> Thanks.
>
> TC.
>
> --
> RV-7 N-128EC (Reserved)
> Left Wing.
>
> Airplane Cam: https://coombsonline.hopto.org/cam1
>
> Tom Coombs
> tom@c...
Author: John <jwkeen@...> Time: Mon Nov 21, 2005 7:41 am PST Link
Safeair have a pitot mast that fits the dynon pitot and mounts the
skin & spar flange with a doubler
http://www.safeair1.com
cheers
John
On 21/11/2005, at 8:58 AM, Tom Coombs wrote:
> Hi folks:
>
> I was tooling around looking at the pitot tube plumbing and fittings.
>
> I have always been a little suspect of the VANS design pitot,
> thinking it
> may be a little flimsy and perhaps also a little ugly in
> practice. For
> grins, I fabbed and bent the tube for the Vans design and and
> actually, it's
> pretty sturdy, it is however a little ugly. My other concern is
> with the
> placement of this tube, with the plans calling for a hole to be
> drilled in
> the spar.
>
> I do have on hand a AN-5814 Compatible 24v heated head and mount
> bracket,
> but I don't have the extension that would push it 6" from the wing
> and also
> a $10 special from Aircraft Spruce, which has two tubes, one clased
> off to
> act as a static.
>
> Now for the question. Has anyone moved the location of the pitot.
> I want
> to move mine inboard 1 bay from the plan position. Also, my
> intention is to
> move it back about an inch on to the wing skin and support it with
> a doubler
> in that area, anyone done anything similar?
>
> On the other hand, if I were to use the 5814, is the extension
> absolutely
> necessary for this wing section? The amateur aerodynamicist in me
> says
> that it probably is for accuracy...
>
> Thanks.
>
> TC.
>
> --
> RV-7 N-128EC (Reserved)
> Left Wing.
>
> Airplane Cam: https://coombsonline.hopto.org/cam1
>
> Tom Coombs
> tom@...
> ------------------------ Yahoo! Groups Sponsor --------------------
> ~-->
> Get fast access to your favorite Yahoo! Groups. Make Yahoo! your
> home page
> http://us.click.yahoo.com/dpRU5A/wUILAA/yQLSAA/1yWplB/TM
> --------------------------------------------------------------------
> ~-
> Van's Air Force - World Wide Wing
> www.vansaircraft.net
> Yahoo! Groups Links
John Keen
RV-7 wings
Gold Coast, Australia
john@...
Author: "Dan Checkoway" <dan@...> Time: Mon Nov 21, 2005 11:39 am PST Link
FYI, I installed my Gretz pitot tube & mount in a bay outboard of the
aileron bellcrank. I don't know what Gretz prescribes now, but I wouldn't
want it in the same bay as the bellcrank. Too much going on in there to
have to mess with pitot connections as well, imho.
)_( Dan
RV-7 N714D (690 hours)
http://www.rvproject.com
----- Original Message -----
From: "gsuit45" <gsuit@...>
To: <RV7and7A@yahoogroups.com>
Sent: Monday, November 21, 2005 6:08 AM
Subject: [RV7Yahoo] Re: Pitot tube selection and placement.
> Tom,
> I'm going through the same decision as you. Take a look at the Gretz Aero
> heated pitot
> tube mounting kit. It sells for $118, and is specifically designed for
> RV's, and works with
> most pitot tubes. It places the pitot aft of the spar, but in the same
> bay as the aileron
> pushtube. You do need the extension, as you want to keep the pitot
> extended into the
> boundary layer of airflow around the wing.
>
> The gretz website is: www.gretzaero.com
>
> Clayton
> RV-7
> Beaumont, TX
>
> --- In RV7and7A@yahoogroups.com, Tom Coombs <n128ec@c...> wrote:
>>
>> Hi folks:
>>
>> I was tooling around looking at the pitot tube plumbing and fittings.
>>
>> I have always been a little suspect of the VANS design pitot, thinking it
>> may be a little flimsy and perhaps also a little ugly in practice. For
>> grins, I fabbed and bent the tube for the Vans design and and actually,
>> it's
>> pretty sturdy, it is however a little ugly. My other concern is with the
>> placement of this tube, with the plans calling for a hole to be drilled
>> in
>> the spar.
>>
>> I do have on hand a AN-5814 Compatible 24v heated head and mount bracket,
>> but I don't have the extension that would push it 6" from the wing and
>> also
>> a $10 special from Aircraft Spruce, which has two tubes, one clased off
>> to
>> act as a static.
>>
>> Now for the question. Has anyone moved the location of the pitot. I
>> want
>> to move mine inboard 1 bay from the plan position. Also, my intention is
>> to
>> move it back about an inch on to the wing skin and support it with a
>> doubler
>> in that area, anyone done anything similar?
>>
>> On the other hand, if I were to use the 5814, is the extension absolutely
>> necessary for this wing section? The amateur aerodynamicist in me says
>> that it probably is for accuracy...
>>
>> Thanks.
>>
>> TC.
>>
>> --
>> RV-7 N-128EC (Reserved)
>> Left Wing.
>>
>> Airplane Cam: https://coombsonline.hopto.org/cam1
>>
>> Tom Coombs
>> tom@c...
> Van's Air Force - World Wide Wing
> www.vansaircraft.net
> Yahoo! Groups Links
Author: Tom Coombs <n128ec@...> Time: Mon Nov 21, 2005 7:18 pm PST Link
Clayton:
Thanks for the info, I took a look at the site and see the parts you are
talking about.
For my part, I am not sure that I am going to install an instrument rated
panel and really don¹t need to install a really expensive heated pitot
system. The heated head that I have is a reclaimed 24v head.
I will let you know what I figure out...
TC.
On 11/21/05 9:08 AM, "gsuit45" <gsuit@...> wrote:
> Tom,
> I'm going through the same decision as you. Take a look at the Gretz Aero
> heated pitot
> tube mounting kit. It sells for $118, and is specifically designed for RV's,
> and works with
> most pitot tubes. It places the pitot aft of the spar, but in the same bay as
> the aileron
> pushtube. You do need the extension, as you want to keep the pitot extended
> into the
> boundary layer of airflow around the wing.
>
> The gretz website is: www.gretzaero.com
>
> Clayton
> RV-7
> Beaumont, TX
>
> --- In RV7and7A@yahoogroups.com, Tom Coombs <n128ec@c...> wrote:
>> >
>> > Hi folks:
>> >
>> > I was tooling around looking at the pitot tube plumbing and fittings.
>> >
>> > I have always been a little suspect of the VANS design pitot, thinking it
>> > may be a little flimsy and perhaps also a little ugly in practice. For
>> > grins, I fabbed and bent the tube for the Vans design and and actually,
>> it's
>> > pretty sturdy, it is however a little ugly. My other concern is with the
>> > placement of this tube, with the plans calling for a hole to be drilled in
>> > the spar.
>> >
>> > I do have on hand a AN-5814 Compatible 24v heated head and mount bracket,
>> > but I don't have the extension that would push it 6" from the wing and also
>> > a $10 special from Aircraft Spruce, which has two tubes, one clased off to
>> > act as a static.
>> >
>> > Now for the question. Has anyone moved the location of the pitot. I want
>> > to move mine inboard 1 bay from the plan position. Also, my intention is
>> to
>> > move it back about an inch on to the wing skin and support it with a
>> doubler
>> > in that area, anyone done anything similar?
>> >
>> > On the other hand, if I were to use the 5814, is the extension absolutely
>> > necessary for this wing section? The amateur aerodynamicist in me says
>> > that it probably is for accuracy...
>> >
>> > Thanks.
>> >
>> > TC.
>> >
>> > --
>> > RV-7 N-128EC (Reserved)
>> > Left Wing.
>> >
>> > Airplane Cam: https://coombsonline.hopto.org/cam1
>> >
>> > Tom Coombs
>> > tom@c...
> Van's Air Force - World Wide Wing
> www.vansaircraft.net
> YAHOO! GROUPS LINKS
>
> * Visit your group "RV7and7A <http://groups.yahoo.com/group/RV7and7A> " on
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Thanks.
TC.
--
Tom Coombs
RV-7 N-128EC (Reserved)
Web Site / Builders Log: http://www.coombs-online.net
Airplane Cam: http://coombsonline.hopto.org/cam1
[Non-text portions of this message have been removed]
Author: Roger Fuller <fullerra@...> Time: Tue Nov 22, 2005 8:10 am PST Link
I don't think you want to move it inboard. Seems to me that the further
inboard you go the more likely it will be impacted by prop wash rendering it
inaccurate. ('course it'd be kinda cool setting in the run up indicating 100
kts + ! )
I purchase the chrome Gretz mount from Steinair. Ship time was reasonable
and quality looks to be very good. I went chrome in anticipation of an
unpainted, polished aircraft. Installation not a problem, and per their
suggestion I moved ot OUT one bay from the access panel.
Roger Fuller
RV-7 Wings - skinning bottom!
Fuselage on deck in the box.
_____
From: RV7and7A@yahoogroups.com [mailto:RV7and7A@yahoogroups.com] On Behalf
Of gsuit45
Sent: Monday, November 21, 2005 6:08 AM
To: RV7and7A@yahoogroups.com
Subject: [RV7Yahoo] Re: Pitot tube selection and placement.
Tom,
I'm going through the same decision as you. Take a look at the Gretz Aero
heated pitot
tube mounting kit. It sells for $118, and is specifically designed for
RV's, and works with
most pitot tubes. It places the pitot aft of the spar, but in the same bay
as the aileron
pushtube. You do need the extension, as you want to keep the pitot extended
into the
boundary layer of airflow around the wing.
The gretz website is: www.gretzaero.com
Clayton
RV-7
Beaumont, TX
--- In RV7and7A@yahoogroups.com, Tom Coombs <n128ec@c...> wrote:
>
> Hi folks:
>
> I was tooling around looking at the pitot tube plumbing and fittings.
>
> I have always been a little suspect of the VANS design pitot, thinking it
> may be a little flimsy and perhaps also a little ugly in practice. For
> grins, I fabbed and bent the tube for the Vans design and and actually,
it's
> pretty sturdy, it is however a little ugly. My other concern is with the
> placement of this tube, with the plans calling for a hole to be drilled in
> the spar.
>
> I do have on hand a AN-5814 Compatible 24v heated head and mount bracket,
> but I don't have the extension that would push it 6" from the wing and
also
> a $10 special from Aircraft Spruce, which has two tubes, one clased off to
> act as a static.
>
> Now for the question. Has anyone moved the location of the pitot. I want
> to move mine inboard 1 bay from the plan position. Also, my intention is
to
> move it back about an inch on to the wing skin and support it with a
doubler
> in that area, anyone done anything similar?
>
> On the other hand, if I were to use the 5814, is the extension absolutely
> necessary for this wing section? The amateur aerodynamicist in me says
> that it probably is for accuracy...
>
> Thanks.
>
> TC.
>
> --
> RV-7 N-128EC (Reserved)
> Left Wing.
>
> Airplane Cam: https://coombsonline.hopto.org/cam1
>
> Tom Coombs
> tom@c...
Van's Air Force - World Wide Wing
www.vansaircraft.net
_____
YAHOO! GROUPS LINKS
* Visit your group "RV7and7A <http://groups.yahoo.com/group/RV7and7A>
" on the web.
* To unsubscribe from this group, send an email to:
RV7and7A-unsubscribe@yahoogroups.com
<mailto:RV7and7A-unsubscribe@yahoogroups.com?subject=Unsubscribe>
* Your use of Yahoo! Groups is subject to the Yahoo!
<http://docs.yahoo.com/info/terms/> Terms of Service.
_____
[Non-text portions of this message have been removed]
Author: "pepeborja925mb" <pepeborja925mb@...> Time: Wed Nov 23, 2005 8:13 am PST Link
I actually like the pitot tube that came with my wing kit. It is
light, very simple, reliable, removable, and does what it is supposed
to do: move the needle on the ASI.
The other options I see cost a great deal of money, require wires, a
circuit breaker, connectors between wing and fuselage, and a switch.
In the end, both of them do the exact same thing with the only
differece being the looks. By using Van's supplied pitot tube I keep
my budget inline and keep the weight where it belongs: off the plane
and in my wallet.
Jose Borja
Elk Mound, WI
ZERO progres, no help in rivetting bottom fuselage Grrrr!
Author: "Dan Checkoway" <dan@...> Time: Wed Nov 23, 2005 1:23 pm PST Link
I agree with Jose. If you don't fly IFR, I don't really see any reason to
go with a heated pitot tube. If I was flying VFR only, I would almost
definitely not have spent the bucks on the heated pitot tube.
If you're VFR, flying through some rain at or near the freezing level -- but
still with enough in-flight visibility to constitute VMC -- it's possible
that you'll get some icing. But if you can see the ground (even out the
sides assuming your windscreen ices over), you can presumably live without
your airspeed indication (imho) for that brief minute while you descend to
warmer temps. I have had this happen on a few occasions when I used to live
& fly in the northeast.
On the flip side -- if you're IFR in IMC, obviously the airspeed indication
is much more critical. And even though we're not required to have a heated
pitot tube, it's my opinion that it's nearly essential. That is, again,
only if you plan on flying in IMC.
In my case, I have a Dynon EFIS-D10. I'm pretty sure airspeed is factored
into the attitude determination logic. If I lose airspeed, my attitude
indication may not be reliable. Again, in VMC, this is not an issue. I can
see the ground, and I can maneuver my plane without reference to airspeed or
even attitude. But in IMC, it's critical in my book. I opted for a heated
pitot tube for this reason.
The only other reason I can think of to install a heated pitot tube even if
you don't plan on flying on instruments would be to increase resale value.
A buyer may want to fly your plane IFR.
)_( Dan
RV-7 N714D (693 hours)
http://www.rvproject.com
----- Original Message -----
From: "pepeborja925mb" <pepeborja925mb@...>
To: <RV7and7A@yahoogroups.com>
Sent: Tuesday, November 22, 2005 5:48 PM
Subject: [RV7Yahoo] Re: Pitot tube selection and placement.
> I actually like the pitot tube that came with my wing kit. It is
> light, very simple, reliable, removable, and does what it is supposed
> to do: move the needle on the ASI.
>
> The other options I see cost a great deal of money, require wires, a
> circuit breaker, connectors between wing and fuselage, and a switch.
>
> In the end, both of them do the exact same thing with the only
> differece being the looks. By using Van's supplied pitot tube I keep
> my budget inline and keep the weight where it belongs: off the plane
> and in my wallet.
>
> Jose Borja
> Elk Mound, WI
> ZERO progres, no help in rivetting bottom fuselage Grrrr!
> Van's Air Force - World Wide Wing
> www.vansaircraft.net
> Yahoo! Groups Links
Author: "pepeborja925mb" <pepeborja925mb@...> Time: Fri Nov 25, 2005 7:35 am PST Link
<SNIP>I agree with Jose. If you don't fly IFR, I don't really see
any reason to go with a heated pitot tube.<SNIP>
Good point Dan, I forgot all about IMC flying for pilots that like
that challenge.
IMHO, having built 1 kit car and now in my 3rd airplane, it seems as
though many first time builders try to achieve their best on their
first effort and build the ultimate machine. That means loading up
on all the goodies without much thought to the missions or flying
style. That was certainly true with the kit car hobby where many
folks end up installing $8000 crate engines when many of us got by
installing used 5.0 engines from donor Mustangs (see
www.ffcobra.com).
That said, there are some guys that are indeed craftsmen by birth and
produce work that is wonderful on their first try, but it is my
experience that most of us are at best average, and that's by the
time we are finished with the airplane.
My only advice to a first time builder is to think very hard about
the choices they are about to make and whether the expense, time
investment, and added weight makes sense for the flying they will
do. The reason I say that is because many of those airplanes will
end up for sale for a variety of reasons. I know two very nice RVs
that were sold due to lost medicals. Also, many pilots have job
commitments and family commitments that keep their airplanes from
seeing a lot of action and thus all gadgets and equipment installed
never get much use.
The builder must think what they want the airplane for. Some want to
build a show plane, some want to build a plane to fly. For those in
the later, if 80% of the flying is done locally chasing the $50
burger, what sense is the installation of an autopilot? The
expense, the added weight, the complexity, the possibility of it
going bad, etc. On the other hand, if 80% of the flying is done x-
country then the AP makes sense. I guess a builder needs to ask the
question: "Is the juice worth the squeeze?" That way he can
logically justify the choice, as opposed to being purely emotional
and driven by the desire to build the ultimate airplane as is the
case with many first time builders (I was one, so I know what goes
through one's mind).
In my case, since the beginning I set up to build a very basic VFR
airplane with minimum instrumentation and zero gadgets. A no frills,
light weight, all manual KIS airplane with simple engine and wood
prop combo, an ASI, EIS (with the idiot light), ALT, handheld radio,
an Ebay xpndr I picked up for cheap, a few switches/breakers, my
handheld GPS and keep that all of that hopefully under $30K.
With that purpose in mind, my decision making process is rather
simple. Selling that airplane would be a snap because most of the
existing fleet demands the pearls of the Virgin Mary, whereas mine
would be priced very reasonable. By keeping it simple I reduce the
liability of having installed equipment that if it were to
malfunction could get a pilot into trouble.
I bet if you were to become a repeat offender and build another RV7
you would make a few different choices that would be driven by the
almost 700 hours you have racked since completion. That experience
would help you build an airplane that suits your current needs good
and proper. In my case, I only have 2 weeks off a year and travel
with a family of 5, so commercial is the way to go. Recreationally
speaking, I fly less than 100 hors per year and mostly locally and
during good weather conditions, thus I could not justify equipping an
airplane like the one you fly. Our missions are totally different:
You travel everywhere in your -7 and I probably won't.
The message I have to share is to build an airplane that matches the
flying needs, rather than the emotional desires to build and have the
ultimate airplane. I have seen countless nice airplanes go for sale
after their owner looses interest or when their flying needs change.
All that work and effort go to the enjoyment of someone else. As we
say in Mexico, "Nadie sabe para quien trabaja" (No one knows who
they work for). The average RV builder will never spend more time
in the air than they spent building the machine. That's something to
think about.
Jose Borja
Elk Mound, WI Stuck with the rear fuselage… little progress made.