 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
PGLong
Joined: 10 Jan 2006
Posts: 37
|
 Posted: Thu Jul 05, 2007 10:33 am Post subject: Landing a loaded RV-4 |
 |
|
Help.......I have an RV-4 and am experiencing landing problems with a rear seater present. I installed a Landoll Harmonic Balancer and according to weight and balance, should be able to tote a 225 pounder and stay within CG limits with correct fuel loads. Even with a 120-150 pound person in the rear seat, the elevator controls are so light it's almost like moving nothing. Not sure if I'm over controlling, but it is so easy to get a hip hop dance down the runway. Friend said to try and use a significant amount of down elevator trim to help. Haven't tried that yet but will next flight. What works for others? Just stick with wheel landings? Lots of friends that would like a ride, but hate to threaten them while I learn new techniques.
Pat Long
PGLong(at)aol.com
N120PL
RV4
Bay City, Michigan
3CM
Do Not Archive
See what's free at AOL.com.
[quote][b]
| | - The Matronics RV4-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV4-List |
|
_________________
Pat Long
RV-4, N120PL
Bay City, MI |
|
| Back to top |
|
 |
dwaynecowles(at)yahoo.com
Guest
|
| Posted: Thu Jul 05, 2007 12:33 pm Post subject: Landing a loaded RV-4 |
|
|
Pat,
I have owned 2 rv's and my current one give me fits with aft cg. I think wheel landings will help you a lot, land a little hot, fly it to the ground. If you experience a lot of bounce (which I do) drop a wing just a little, let one wheel hit then the other. Less likely to bounce.
My 2 cents.
Dwayne
PGLong(at)aol.com wrote: | Quote: | Help.......I have an RV-4 and am experiencing landing problems with a rear seater present. I installed a Landoll Harmonic Balancer and according to weight and balance, should be able to tote a 225 pounder and stay within CG limits with correct fuel loads. Even with a 120-150 pound person in the rear seat, the elevator controls are so light it's almost like moving nothing. Not sure if I'm over controlling, but it is so easy to get a hip hop dance down the runway. Friend said to try and use a significant amount of down elevator trim to help. Haven't tried that yet but will next flight. What works for others? Just stick with wheel landings? Lots of friends that would like a ride, but hate to threaten them while I learn new techniques.
Pat Long
PGLong(at)aol.com
N120PL
RV4
Bay City, Michigan
3CM
Do Not Archive
See what's free at [/b] |
[/quote]
8:00? 8:25? 8:40? [url= http://tools.search.yahoo.com/shortcuts/?fr=oni_on_mail&#news] Find a flick[/url] in no time
with the[url= http://tools.search.yahoo.com/shortcuts/?fr=oni_on_mail&#news]Yahoo! Search movie showtime shortcut.[/url] [quote][b]
| | - The Matronics RV4-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV4-List |
|
|
|
| Back to top |
|
|
esmith6(at)satx.rr.com
Guest
|
| Posted: Thu Jul 05, 2007 3:06 pm Post subject: Landing a loaded RV-4 |
|
|
Pat................I've had my RV-4 for 14yrs, and somewhere in mid yrs, I had the same problem you mentioned.
Found out two things: 1. My pitot static system was in error...If I indicated 60mph, I was actually doing 82.2mph...With a GIB (guy in back) it still wanted to fly...I don't know why, but solo it never would do the porpoise routine...Anyway I checked the pitot tube for bugs and etc...(used air and blew from behind the inst. panel backwards, so they would come out)...Then I put little stainless steel clamps on every connection in the entire system.
2. Fly often in that GIB configuration, get your proficiency peaked...It worked for me...We don't fly enough............CHEERS!!!!
Pat,
I have owned 2 rv's and my current one give me fits with aft cg. I think wheel landings will help you a lot, land a little hot, fly it to the ground. If you experience a lot of bounce (which I do) drop a wing just a little, let one wheel hit then the other. Less likely to bounce.
My 2 cents.
Dwayne
PGLong(at)aol.com (PGLong(at)aol.com) wrote:
| Quote: | | Quote: | Help.......I have an RV-4 and am experiencing landing problems with a rear seater present. I installed a Landoll Harmonic Balancer and according to weight and balance, should be able to tote a 225 pounder and stay within CG limits with correct fuel loads. Even with a 120-150 pound person in the rear seat, the elevator controls are so light it's almost like moving nothing. Not sure if I'm over controlling, but it is so easy to get a hip hop dance down the runway. Friend said to try and use a significant amount of down elevator trim to help. Haven't tried that yet but will next flight. What works for others? Just stick with wheel landings? Lots of friends that would like a ride, but hate to threaten them while I learn new techniques.
Pat Long
PGLong(at)aol.com
N120PL
RV4
Bay City, Michigan
3CM
Do Not Archive
See what's free at [/b]
|
8:00? 8:25? 8:40? Find a flick in no time
with theYahoo! Search movie showtime shortcut. | Quote: |
href="http://www.matronics.com/Navigator?RV4-List">http://www.matronics.com/Navigator?RV4-List
href="http://forums.matronics.com">http://forums.matronics.com
|
|
[quote][b]
| | - The Matronics RV4-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV4-List |
|
|
|
| Back to top |
|
|
ceengland(at)bellsouth.ne
Guest
|
| Posted: Thu Jul 05, 2007 4:03 pm Post subject: Landing a loaded RV-4 |
|
|
PGLong(at)aol.com wrote:
| Quote: | Help.......I have an RV-4 and am experiencing landing problems with a
rear seater present. I installed a Landoll Harmonic Balancer and
according to weight and balance, should be able to tote a 225 pounder
and stay within CG limits with correct fuel loads. Even with a 120-150
pound person in the rear seat, the elevator controls are so light it's
almost like moving nothing. Not sure if I'm over controlling, but it is
so easy to get a hip hop dance down the runway. Friend said to try and
use a significant amount of down elevator trim to help. Haven't tried
that yet but will next flight. What works for others? Just stick with
wheel landings? Lots of friends that would like a ride, but hate to
threaten them while I learn new techniques.
Pat Long
PGLong(at)aol.com
N120PL
RV4
Bay City, Michigan
3CM
Do Not Archive
Hi Pat,
|
I've owned 2 -4's, both with 160hp/wood prop, very light empty weight, &
the 1st had completely different characteristics from the one I'm flying
now. FWIW, 225 in the back seat is pushing the envelope in a -4. Yes,
I've done it (did it this afternoon for my biennial flight review) but
it really does change the airplane with that much weight in the back.
I'm too lazy to type a long epistle, but email me your phone # or you
can call me at 601-879-9596 & I'll be glad to talk about why I think the
plane does what it does with a lot of weight in back. (Think flaps.)
Charlie
| | - The Matronics RV4-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV4-List |
|
|
|
| Back to top |
|
|
baremetl(at)gvtc.com
Guest
|
| Posted: Thu Jul 05, 2007 5:03 pm Post subject: Landing a loaded RV-4 |
|
|
Pat,
I have the Landoll steel ring with a wood prop and light-weight starter. I'm ok with 225lbs. in the rear as long as the baggage compartment is empty. The stick forces are quite light, but manageable if I have my forearm pressed against my thigh to brace my arm. I always 3-point, (or at least attempt to), and occasionally skip a little, but all in all feel comfortable. Keep practicing, it will come. And be sure to keep your speed low. Excess speed makes it much more difficult.
Ivan Haecker -4 1370 hrs. S. Cen. TX
[quote] ---
| | - The Matronics RV4-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV4-List |
|
|
|
| Back to top |
|
|
daubuchon(at)volcano.net
Guest
|
| Posted: Thu Jul 05, 2007 8:10 pm Post subject: Landing a loaded RV-4 |
|
|
Hi Pat,
I have about 500 hours on my 4, and this is what I have picked up over the years,,
225lbs,, for MY airplane, is pretty much at the maximum I would have in the rear seat.
My basic, "no-brainer" limit is 200lbs. Anything over that, then I have to start some serious figuring. That 200lb self-imposed limit assumes my usual load of stuff in the baggage area,, small tool kit, canopy cover, quart of oil,, etc. Above 200lbs,,, everything in the baggage area comes out.
Next is fuel.
As the fuel burns the aircraft cg slips aft, which exacerbates the situation. So I will always start with full tanks and keep the legs short with a heavy load in the back
As mentioned in your post, the forward trim trick is very important. It gives the stick somewhat of a "preload," for lack of a better term and negates most of the effects of hardware slop in the control system. As an added bonus, after time,,, you will be able to get a feel for the effectiveness of the trim, and adjust the airspeed over the fence accordingly.
Just my two cents,,
Derrick Aubuchon
RV-4: N184DA
Jackson/Westover -Amador County (O70)
daubuchon(at)volcano.net (daubuchon(at)volcano.net)
On Jul 5, 2007, at 11:25 AM, PGLong(at)aol.com (PGLong(at)aol.com) wrote:
[quote] Help.......I have an RV-4 and am experiencing landing problems with a rear seater present. I installed a Landoll Harmonic Balancer and according to weight and balance, should be able to tote a 225 pounder and stay within CG limits with correct fuel loads. Even with a 120-150 pound person in the rear seat, the elevator controls are so light it's almost like moving nothing. Not sure if I'm over controlling, but it is so easy to get a hip hop dance down the runway. Friend said to try and use a significant amount of down elevator trim to help. Haven't tried that yet but will next flight. What works for others? Just stick with wheel landings? Lots of friends that would like a ride, but hate to threaten them while I learn new techniques.
Pat Long
PGLong(at)aol.com (PGLong(at)aol.com)
N120PL
RV4
Bay City, Michigan
3CM
Do Not Archive
See what's free at AOL.com.
| Quote: |
href="http://www.matronics.com/Navigator?RV4-List">http://www.matronics.com/Navigator?RV4-List
href="http://forums.matronics.com">http://forums.matronics.com
|
[b]
| | - The Matronics RV4-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV4-List |
|
|
|
| Back to top |
|
|
James Baldwin
Joined: 16 Jan 2006
Posts: 23
|
| Posted: Thu Jul 05, 2007 9:22 pm Post subject: Landing a loaded RV-4 |
|
|
James Baldwin wrote:
| Quote: | Pat -
From a theoretical point of view I'll give you one answer: the real
simple version. I don't have my reference book in front of me but what
|
we're obviously talking about here is called static longitudinal
stability. It has everything to do with what you are experiencing and
is strictly a function of loading and the resultant location of the
center of gravity (CG). As the CG moves rearward it approaches the
location of the lift line of the main wing. The tail, for positive
static stability, acts downward and (I am ignoring some cases where
unusual moments or other aerodynamic effects alter this case) is the
variable controlled by the force at the control, or in the case of an
RV, the stick. Obviously as we all experience, the forces required by
the horizontal tail vary with airspeed, thus the need for trim. As the
CG gets close to the lift line location longitudinally, due to passenger
or baggage loading, the force required downward by the horizontal tail
is less and less. Since the downward force required is becoming smaller
as we load more into the rear seat and baggage area it becomes more
sensitive to small stick movements. At the neutral point the tail does
nothing but you'd better HANG ON!
| Quote: | That's a real simplistic description of what is going on here. RV4s
with lightweight starters, wood props, no mags, etc already have a
|
rearward bias to the location of the CG and thankfully the arm for these
weight savings is pretty small. I know of one RV6 in particular that
has the opposite problem since he is using an IO360 angle valve with a
CS prop. He runs out of elevator in the flare! He can't do a full
stall landing.
What's the solution? Well, put a CS prop on it. Put an O360 up there.
Is the battery located way up front? Doing something like this is
pretty radical so the other way to look at it is to actually measure the
location of the CG and compare it to what Van dictates as practical
limits. I'm going to guess that you guys are exceeding the rearward
limit that Van specifies as acceptable for decent handling. I don't
have the weight and balance information in front of me but if I remember
I think the limits were something like 15 to 30% MAC (of the mean
aerodynamic chord). The way you find out where you are REALLY flying is
to get three scales and fully load the airplane in a level attitude just
the way the builder did when he finished building, only do it with a
load the way you actually fly it. You and your pax (or weights) sit in
there and then you do the math after getting the weights from the
scales. Now you know what the problem is if my suspicions are correct:
you are outside the weight and balance limits set by Van for your
aircraft. Van knew enough to put a margin in there for all of us but he
also flew enough stuff to know he had to demand handling characteristics
for the "least common denominator" pilot. If I were you, I'd find out
where my CG REALLY is and quit trying to defeat the physics of flight we
all must deal with. Out of the envelope operation can only lead to
disaster when coupled with other factors such as wind, weather, low
fuel, short runways, engine out, etc. Using a forward trim does not
change the effects of a poor loading scenario. In fact it does not
change the slope of the plot of the longitudinal stability (dcm/cg) line
either, it just makes the controls feel better.
| Quote: | My guess is you'll discover you are operating your airplane outside
the planned envelope and probably you need something more capable. Go
|
see John Harmon -- he has this thing called a Rocket. JBB
| Quote: |
ps -- a big ps here: I can imagine there maybe might be one or two
cases out there where some error in building might bias the CG or wing
|
location which would adversely affect the normal passenger load handling
characteristic, but probably not, it's probably plain and simple weight
and balance.
| Quote: |
PGLong(at)aol.com wrote:
> Help.......I have an RV-4 and am experiencing landing problems with a
rear seater present. I installed a Landoll Harmonic Balancer and
|
according to weight and balance, should be able to tote a 225 pounder
and stay within CG limits with correct fuel loads. Even with a 120-150
pound person in the rear seat, the elevator controls are so light it's
almost like moving nothing. Not sure if I'm over controlling, but it is
so easy to get a hip hop dance down the runway. Friend said to try and
use a significant amount of down elevator trim to help. Haven't tried
that yet but will next flight. What works for others? Just stick with
wheel landings? Lots of friends that would like a ride, but hate to
threaten them while I learn new techniques.
| | - The Matronics RV4-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV4-List |
|
|
|
| Back to top |
|
|
smokyray(at)yahoo.com
Guest
|
| Posted: Fri Jul 06, 2007 2:58 am Post subject: Landing a loaded RV-4 |
|
|
Jim,
In simple tems I use a limit of 200lbs total aft of the roll bar in my 160HP wood prop RV4.Carrying heavier folks I add fuel which helps CG. A Landoll dampener, changing to an Odessey batter and mounting it on the firewall all helped.
I personally only give rides to cute girls under 115 lbs...your call...
Rob Ray
15,000 gallons burned, RV4
jamesbaldwin(at)dc.rr.com wrote:
[quote]--> RV4-List message posted by: jamesbaldwin(at)dc.rr.com
James Baldwin wrote:
| Quote: | Pat -
From a theoretical point of view I'll give you one answer: the real
simple version. I don't have my reference book in front of me but what
|
we're obviously talking about here is called static longitudinal
stability. It has everything to do with what you are experiencing and
is strictly a function of loading and the resultant location of the
center of gravity (CG). As the CG moves rearward it approaches the
location of the lift line of the main wing. The tail, for positive
static stability, acts downward and (I am ignoring some cases where
unusual moments or other aerodynamic effects alter this case) is the
variable controlled by the force at the control, or in the case of an
RV, the stick. Obviously as we all experience, the forces required by
the horizontal tail vary with airspeed, thus the need for trim. As the
CG gets close to the lift line location longitudinally, due to passenger
or baggage loading, the force required downward by the horizontal tail
is less and less. Since the downward force required is becoming smaller
as we load more into the rear seat and baggage area it becomes more
sensitive to small stick movements. At the neutral point the tail does
nothing but you'd better HANG ON!
| Quote: | That's a real simplistic description of what is going on here. RV4s
with lightweight starters, wood props, no mags, etc already have a
|
rearward bias to the location of the CG and thankfully the arm for these
weight savings is pretty small. I know of one RV6 in particular that
has the opposite problem since he is using an IO360 angle valve with a
CS prop. He runs out of elevator in the flare! He can't do a full
stall landing.
What's the solution? Well, put a CS prop on it. Put an O360 up there.
Is the battery located way up front? Doing something like this is
pretty radical so the other way to look at it is to actually measure the
location of the CG and compare it to what Van dictates as practical
limits. I'm going to guess that you guys are exceeding the rearward
limit that Van specifies as acceptable for decent handling. I don't
have the weight and balance information in front of me but if I remember
I think the limits were something like 15 to 30% MAC (of the mean
aerodynamic chord). The way you find out where you are REALLY flying is
to get three scales and fully load the airplane in a level attitude just
the way the builder did when he finished building, only do it with a
load the way you actually fly it. You and your pax (or weights) sit in
there and then you do the math after getting the weights from the
scales. Now you know what the problem is if my suspicions are correct:
you are outside the weight and balance limits set by Van for your
aircraft. Van knew enough to put a margin in there for all of us but he
also flew enough stuff to know he had to demand handling characteristics
for the "least common denominator" pilot. If I were you, I'd find out
where my CG REALLY is and quit trying to defeat the physics of flight we
all must deal with. Out of the envelope operation can only lead to
disaster when coupled with other factors such as wind, weather, low
fuel, short runways, engine out, etc. Using a forward trim does not
change the effects of a poor loading scenario. In fact it does not
change the slope of the plot of the longitudinal stability (dcm/cg) line
either, it just makes the controls feel better.
| Quote: | My guess is you'll discover you are operating your airplane outside
the planned envelope and probably you need something more capable. Go
|
see John Harmon -- he has this thing called a Rocket. JBB
| Quote: |
ps -- a big ps here: I can imagine there maybe might be one or two
cases out there where some error in building might bias the CG or wing
|
location which would adversely affect the normal passenger load handling
characteristic, but probably not, it's probably plain and simple weight
and balance.
| Quote: |
PGLong(at)aol.com wrote:
> Help.......I have an RV-4 and am experiencing landing problems with a
rear seater Looking for earth-friendly autos?
|
Browse Top Cars by "Green Rating" at Yahoo! Autos' Green Center. [quote][b]
| | - The Matronics RV4-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV4-List |
|
|
|
| Back to top |
|
|
splitess(at)suscom-maine.
Guest
|
| Posted: Fri Jul 06, 2007 3:38 am Post subject: Landing a loaded RV-4 |
|
|
Pat,
What is your empty weight for your RV4? Mine is 995, which is about 80 lbs heavier than the planned target of 905-913. With that in mind and running my own W&B numbers I never even considered anyone over 150 pounds for the rear pax with full fuel and an empty rea comparment. I only have about 25 hours in mine, so some insight would be valuable. I have an 320H2D up front with fixed pitch prop, so I am pretty much standard with a standard VFR panel.
Steve
D. Steven Schlieper
8 Homeplace
Topsham, Maine 04086
Tony Blair's comment...
In case we find ourselves starting to believe all the anti-American sentiment
and negativity; we should remember England's Prime Minister Tony Blair's words during a
recent interview. When asked by one of his Parliament members why he believes so much in
America, he said: "A simple way to take measure of a country, is to look at how many want in...
and how many want out. Only two defining forces have ever offered to die for you:
1. Jesus Christ
2. The American G. I.
One died for your soul, the other for your freedom."
[quote] ---
| | - The Matronics RV4-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV4-List |
|
|
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
