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pilot28906

Well Known Member
I have the tool kit from "plane tools" enroute and will be ordering the tail section for a 7A soon and see that manual or electric elevator trim has to be decided on early. I have flown mostly manual trim and wonder if the extra $ is worth it. Any opinions appreciated.

Thanks,
John
 
Manual v. electric trim

Fairly new poster here, with exactly the same question.

Looking over the RV-7A order form, I need to decide if I want the electric elevator trim.

I'm leaning toward electric, with one of those chinese hat switches on the joystick; but, I'd love to hear some input from a few veteran RV pilots.

Regards all - - Seaplaner
 
I've only flown an RV with electric (Dans) but I'd go with that. I don't like the Vernier control for trim, and if they had a more 'standard' trim wheel like Cesspools or Pipers I'd do it, but not the vernier.
 
trim

Well, I just took delivery of my 7 emp...ordered the electric trim
mainly because this is the 21st century! No actually i've been reachin' between the seats of a rented Cessna for over 10 years and MY PLANE is going to have electric trim (just like the big airplanes) :rolleyes:
 
Electric or manual trim

I have an RV6 with manual trim and I would install it again due to simplicity but it does require a very light touch at cruise speeds. A friend also has an RV6 but with electric trim. He likes his as well but it also is extremely sensitive to adjustments at cruise. The unit is so sensitive at cruise he almost has to just "tap" the cooly hat button to adjust it and the reverse is true at high speeds. If you decide in this option you should look into a trim speed adjustment option which is meant to solve this problem.
 
From studying the plans on my -7, I think the only difference between electric trim and manual in the empenage kit is the trim servo, trim tab horn shape (you shape it yourself based on what kind of trim you want), and a couple of holes you can easily drill later. What I'm getting at is that I think you can just order the emp without the electric trim, and then decide later which way you want to go. You would just leave some things undrilled and you'd finish the trim tab after you decided.

I may be missing something obvious here but it's just a thought. Personally, I ordered electric trim because I wanted something other than aluminum and fiberglass to show up in the emp kit. LOL....that's as good a reason as any, right? :D
 
Manual

If you go with electrical trim it is probably easier to install but you will miss out on one of the sweetest man-machine interfaces I have experienced. You can feel the smooth life-like response of the plane to slight movements of the knob. It is not like any other plane I have flown; there is no detectable deadband in the response. Using electric pitch trim on my RV-6A would be as disappointing as electric switches to control the ailerons - it would work but some of the sensual pleasure of controlled flight would be lost. Then there is that reliability thing - I would not want to fly my plane without pitch trim.

Bob Axsom
 
Many people will advocate the simplicity of manual systems. Undeniable. But here's my rationale for all electric, and for having everything on the stick...it makes formation flying SAFER imho.

I can make a formation landing, including a frequency change, trimming, and flaps, without moving my hands. If this is not a priority to you then I'd say it doesn't matter much whether you go electric or manual.
 
Facts, Forks, and Fallacies

seaplaner said:
Fairly new poster here...........I'm leaning toward electric, with one of those chinese hat switches on the joystick; but, I'd love to hear some input from a few veteran RV pilots..........Regards all - - Seaplaner
Click to expand...
Seaplaner,

Building an airplane can bring out the Walter Mitty in us, and why not? Few things in life rival the dream of actually building an airplane with our own two hands. Do we not dream while making "airplane noises" sitting on pillows and plywood in the unfinished cockpit of our future RV? My experience is thus. I've continued to own a Cessna 150 for 18 years and as you probably know, it sports a manual, vertically mounted trim wheel located low on the center console. Works like a champ and is virtually bulletproof. Still, you have to reach down for it with the right hand while holding the yoke with the left hand. Now I've sat....only sat.....in the cockpit of many high performance jet fighters....particularly F-15's and F-18's I once helped build. Did a lot of dreaming there too, often during an entire lunch period. I always loved the look and military no-nonsense feel of the china hat perched atop the joystick grip. Personally, I was not the least bit conflicted when the day finally came when I had the opportunity to check the appropriate box on the empennage kit order form.
I went on to install 2-axis electric trim in my RV on an Infinity joystick grip and never looked back. I truly enjoy the simple act of keeping the airplane in balanced flight with little more than the slightest thumb manipulation. If you inquire a bit deeper with those RV'ers who claim electric trim is too sensitive....just ask it they thought or bothered to install the MK-111 speed controller to tame electric trim's inherent sensitivity. Chances are, they did not. Whether in high speed cruise or flying the pattern, my electric trim performs as well as I could possibly ask. Come to think of it...how on Earth could a Mach 2+ jet possibly deal with trim issues thoughout its operating regime without some sort of mitigating controller?
In the end, like in the other on-going perennial debates, minds will not be changed. But unlike those with flying RV's, you are at an early fork in the construction road. Whichever path you decide upon next will serve you quite well...manually or electrically. Be forewarned....there are many, many forks ahead. Happy building!

Rick Galati RV-6A "Darla" 124 hours
 
Electric Trim or Fulfilling fantasies

Rick, Very well said. I have a little time in military jets with the hat switch. Much more time in Cessnas with the vertical mounted wheel. The manual trim may work just as well, but it does not fulfill the fantasies as well as the hat switch.
 
I like the electric trim because.....

The one thing I did not like about the manual trims that I have seen and tested on RV's is that the trim tab seems sloppy. By that I mean it is not tight and firm and there is some play.

The electric trim on my RV-8 however, is rock hard. After building high speed model sailplanes for years, there is one thing that I insist on, and that is negative control slop. I have actually experienced horizontal stabilizer flutter on a Pitts one day while performing a loop over a cloud deck. I was just coming over the top when it felt like a giant hand began shaking the elevator like a dog with a bone. I looked back, and to my horror, the entire stab was oscillating up and down along with the elevators. Meanwhile, I was clinging on to the stick like grim death and I reached over and pulled the throttle off, and as I was easing down the back side of the loop I rolled from inverted to upright and the shaking stopped! WHEW!!!

After my heart slowed down, I glided softly in to a landing at a nearby field and shut down. Upon examining the elevators, I noticed that the trim tab cable had bowed into a semicircle where it exited the sheathing and that was what had initiated the shaking, an oscillating trim tab.

Anyway, I really, really, like the firmness of the electric trim on the RV's as opposed to the manual cables. Somehow, that bowden cable provides inherent slop.

I also know that it would be not very nice to be stuck out in the boonies with no electrics and your electric trim tab would now be frozen in place. But those little trim motors will run off of a nine volt battery. So, A guy could possibly wire in a little aux circuit powered by a nine volt battery to get the tab back to neutral for the trip home. Something to think about. Perhaps it could be wired with the unused Ray Allen actuator switch that would not be used with the Coolie Hat switch.

Cheers, Pete
 
Somebody has to chime in for manual trim, so here I go...

It is cheap, light, simple and bulletproof. I too like to fly with electric trim, but only, ONLY if I have a mechanical backup. If the electric quits your stuck in whatever trim position you have. It happened last year to a friend while making high-speed passes in his 8, got stuck in the 200+ position. He brought it back in, but he's ex-Air Force 20 years. I wouldn't want to try that.

Whoever it was that said they didn't like the vernier trim control, I'd wager that they've never tried it. It is a very natural feel, very intuitive and easy to get used to. And there is no slop in the system, I don't know where that idea came from.

And I'm going to disagree with Dan about having a bunch of stuff on the stick. Unless you fly for a living (or as much as Dan does... ;) you will likely not develop the skills and muscle memory to hit all those buttons and switches at the right time. Yes you can do all kinds of stuff with your hand on the stick, but you can also hit down flaps at cruise speed while meaning to hit trim. Or you could hit the starter button while trying to "flip-flop" the radios. Or flip flop when you meant to PTT and wonder why lead is not talking anymore... you get the point. If you're one of those who thinks you'll never make that mistake or get flustered, then chances are you've never flown with another airplane 5 feet away. I fly lots of formation with only one button on my stick, PTT.

Of course I may be all wet, but consider my opinion. KISS is a very valid principle.
 
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sprucemoose said:
And I'm going to disagree with Dan about having a bunch of stuff on the stick. Unless you fly for a living (or as much as Dan does... ;) you will likely not develop the skills and muscle memory to hit all those buttons and switches at the right time. Yes you can do all kinds of stuff with your hand on the stick, but you can also hit down flaps at cruise speed while meaning to hit trim. Or you could hit the starter button while trying to "flip-flop" the radios. Or flip flop when you meant to PTT and wonder why lead is not talking anymore... you get the point. If you're one of those who thinks you'll never make that mistake or get flustered, then chances are you've never flown with another airplane 5 feet away.
Click to expand...

5 feet is pretty tight formation :) Many of the RV's that I regularly fly formation with have at least pitch/roll trim on stick, several have flaps. I've heard (and made) a lot of debrief excuses but have yet to hear 'my stick confused me'...

I think that it is true that you 'could' mess up all of those things, my experience (as a non military/non commercial pilot) has been that having the controls on the stick is intuitive, safe and reduces workload. I love not looking down to adjust things or change frequencies. I don't have the starter on the stick but I can even see the arguments to having it there.

There is a reason the military does HOTAS (hands on throttle and stick) and it's not because it looks cool, it reduces workload.

All that said this thread was about manual/electric. I love the electric trim on the stick but I have had a trim failure. I lost down trim direction in cruise and while trying to figure it out ended up with a fair amount of up trim which was OK for landing. This made me rethink my emergency proceedures a bit. I practice various trim 'scenarios' periodically.


Chuck
 
I've only flew planes with manual trim. Why I then selected electric: trim handle won't bother you (hatswitch I quess) and take any space from center and when it's in the stick you have one extra hand available all the time.
 
pilot28906 said:
I have the tool kit from "plane tools" enroute and will be ordering the tail section for a 7A soon and see that manual or electric elevator trim has to be decided on early. I have flown mostly manual trim and wonder if the extra $ is worth it. Any opinions appreciated.

Thanks,
John
Click to expand...

Since you asked about is it worth the "extra $", here's my take:

I originally ordered electric and have since sold my electric and am putting in a manual. I made the choice (and change) because I like simple and I like to "feel" the controls. And I really liked how intuitive and comfortably placed everything was when I sat in Vans' RV9 with the manual trim. That said, saving a couple hundred bucks is worth something too. A lot of people will say "don't worry about a couple hundred bucks. After all you're going to be spending XXX thousands on this plane so a couple hundred won't really make much difference in the long run." I argue this same point on some parts of my project too!

Since you are just now starting, though, keep in mind that this mindset can really adds up over time. You will be making lots of $$ decisions/choices over the course of this project. A couple hundred here, a couple hundred there, and all of a sudden you've discovered the difference between a $50K RV and a $75K RV. I even saw a website where I guy spent $65K-75K on his panel and engine alone after he had started the project with the idea that he was going to build a low-cost RV. To each his own, and he does have a REALLY nice panel, but I'm sure it turned into a $100K project for him. Not cheap, by any measure. The very insidious part of this hobby is that it's easy to rationalize going with more expensive options since it's an expensive hobby to begin with.

Again, your question probably should be answered by personal preference more than $$, but I thought I'd add this since no one else seems to have picked up on that part of your question. For me, dollars and personal preference both pointed the same direction.

Good luck, and have fun building.
 
Had electric on my RV-6A, and then flew an RV-6A with manual, and couldn't believe how much I preferred manual. Hands down, two thumbs up, etc, etc, for manual trim. I would install manual trim for the next ten airplanes if I were to build them.
 
Manual flaps, manual trim (pitch & roll), now and forever.
My preference; Your preference may vary.
Mel...DAR
 
I'm going manual

I think I have made a decision. I will be going manual due to not having to worry about not having trim if there is an electrical problem. I know this probably does not happen often but I feel better about the manual sytem. Alpinelakespilot2000, thanks for the comments; this was my thinking too. It's only a few $100 but a few hundred bucks on every decision will add up over the course of the plane and I do not plan on building a $100K plane. Thanks for all the comments, I'm sure the electrical system is fine too.

John
 
I know a guy that took his -4 up and flew it with both extremes of pitch trim in, and it was both flyable and landable. That was the deciding factor in me doing electric. I'm not as worried about trim runaway since it is flyable...
 
osxuser said:
I know a guy that took his -4 up and flew it with both extremes of pitch trim in, and it was both flyable and landable. That was the deciding factor in me doing electric. I'm not as worried about trim runaway since it is flyable...
Click to expand...
I re-did this trim test a few weeks ago after building a new trim tab. I flew at 120+ knots indicated with the trim tab at each extreme. Don't let go of the stick, sure, but it's definitely manageable -- at least in my RV-7. And I didn't even eat my spinach that morning.
 
That is hardly the most severe situation

dan said:
I re-did this trim test a few weeks ago after building a new trim tab. I flew at 120+ knots indicated with the trim tab at each extreme. Don't let go of the stick, sure, but it's definitely manageable -- at least in my RV-7. And I didn't even eat my spinach that morning.
Click to expand...

That is good to know but hardly surprising - I suspect many student pilots fly their early flights out of trim. Let's say it is dark, your airport is closely surounded by hills or mountains (I'm not talking about the vast distance from Chino to the nearest mountains but less than a mile on all sides like Drake Field), you are a little tired from working all day, you takeoff on what you expect to ba a routine flight with an IFR departure into a low ceiling with a Vx climb, handling radios, vectors, etc. and you level off at your "expect higher in 10" altitude and are unable to remove the nose up trim. This type of maximum transition situation is what will kill you, not straight and level slow speed cruise test situation.

Bob Axsom
 
Manual for me.

I'm not influenced by the money aspect...even if electric and manual were the same price I'd go manual elevator trim. I have both manual and electric in the Piper Archer I fly and I use the manual exclusively for the feedback it provides. The coolie hat winds you too far one way...then too far the other way...drives me mad.....not enough "feeling" in the electric system. And that's when the wretched thing is working properly and not sticking. After I flew an RV7A with manual trim I was even more convinced...it worked just great...I was impressed with the feel.
 
Bob Barrow said:
I'm not influenced by the money aspect...even if electric and manual were the same price I'd go manual elevator trim. I have both manual and electric in the Piper Archer I fly and I use the manual exclusively for the feedback it provides. The coolie hat winds you too far one way...then too far the other way...drives me mad.....not enough "feeling" in the electric system. And that's when the wretched thing is working properly and not sticking. After I flew an RV7A with manual trim I was even more convinced...it worked just great...I was impressed with the feel.
Click to expand...

I'm the opposite. Once I started flying an Arrow with electric trim, I never went back. I've preferred the 6A and 9A with electric trim. Just an opposite view... :)
 
Bob Axsom said:
...an IFR departure...unable to remove the nose up trim.
Click to expand...
Bob, you make a very good point about loss of trim/out of trim while in IMC. I need to make a note to practice that next time I'm under the hood.
 
Bump

Just getting my order ready send off and figured I better decide on trim option. I'm having trouble deciding. I've never flown an electric trim, but have been exposed to a very sloppy and stiff manual system. if the Vans manual system is smooth, I will happily save the $240....or electric sounds like a nifty wat to go. BTW, I'm building a simple Day/night VFR RV-7. Lots of motor, but not much else. I like the "less is more" mindset.

Looks like from the previous posters, it is fairly even split. Thanks for nothing you guys :D
 
Save the money and go manual trim on elevator and aileron. They both work fine and are easy to adjust. I was always chasing electric trim. They never quite stopped where I wanted them to. The manual trim is so easy to just tweek that "just enough" into them. And you don't need any indicator, either. There! Tie Breaker!!!

Roberta

PS: I wish the flaps were manual, too!!
 
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My manual trim has been working great for over 13 years. If I built a new airplane today (which I am), I would still go with manual trim. Of course I also have manual roll trim, manual flaps and no auto pilot.
BTW Roberta, you can still go to manual flaps. All you have to do is modify the flap weldment. The dimensions are in the -6 plans. It's not a difficult mod.
 
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Thanks, Mel. If that motor ever gives me trouble, I may just do that. I don't mind the electric flaps nearly as much as the trim.

Roberta
 
Roberta - ditto

robertahegy said:
Save the money and go manual trim on elevator and aileron. They both work fine and are easy to adjust. I was always chasing electric trim. They never quite stopped where I wanted them to. The manual trim is so easy to just tweek that "just enough" into them. And you don't need any indicator, either. There! Tie Breaker!!!

Roberta

PS: I wish the flaps were manual, too!!
Click to expand...
If manual flaps had been available on my QB -7A I would have ordered it. I liked it better on Cherokees, C-172's, etc. I just love the feel of the RV manual trim. I am not sure about electric, but with manual, you have two variables that you can control it with: force and distance. You have inherent feedback force as part of the technique. Consequently, you have more fine control with no learning curve. I also don't buy the everything-on-the-stick argument. Good for others, maybe, but not for me. I don't want to hit the wrong knob or button while bouncing around or just tired. Two cents plain.
 
We've gone Manual... I've got loadsa hours on Mil FJs with Electric Trim, and now Airliners as well - in fact latest Airliner has no Trim... but then it is French :p

We've gone Manual just to get back into real flying, and feel the aircraft... even a good electric trim is never "quite right". However, I suspect for a private pilot who has only flown "manual trim", the electric option is a luxury they have not yet experienced...
 
$$$$$$$$

If it matters....$240 for the electric trim and I believe an $80 credit for not shipping the manual cable(?) with the fuse.

More importantly, it's your plane that you're building, build it your way, just like the BurgerKing commercial.
(still installing electric trim) :D
 
Shouldn't this be in the unending debate section?

I elected to go with manual trim in my -9 for one reason, every rental plane I have flown with electric trim has had a problem with it at one time or another.
All the different airplanes (there are over 40 of them now) that I have flown with manual trim, the trim has worked every time. (Some not so effectively, a J-3 comes to mind, but they worked.)

If manual flaps had been available for the -9, I would have installed those too but in talking with Van's, the RV-9 flaps are so long that putting the flaps down was a bit difficult, thus another reason for electric flaps only.

Mel said:
My manual trim has been working great for over 13 years. If I built a new airplane today (which I am), I would still go with manual trim. Of course I also have manual roll trim, manual flaps and no auto pilot.
BTW Roberta, you can still go to manual flaps. All you have to do is modify the flap weldment. The dimensions are in the -6 plans. It's not a difficult mod.
Click to expand...
 
I honestly think that the reason Van dropped the manual flaps was so he wouldn't have to offer 2 options. Note that he also doesn't offer them on the -7. Even though the -9 flaps are longer, they are narrower and slotted. I really think that manual flaps would work fine on the -9. If I built a -9, I would definitely try them.
 
Always keep in mind, that manual flaps on an RV, are not like reaching forward for the flap handle on a Piper. It's reaching down between the seats, and not all that great with a passenger.

I prefer elec on an RV. It's no contest IMO.

L.Adamson
 
Why is reaching between the seats a problem? I've flown my -6 for almost 14 years and 98% of that time with a passenger. No problem. Now if we're talking the -4, manual flaps have a problem with the passenger's left foot, but on the sbs there's no problem.
 
Mel said:
Why is reaching between the seats a problem? I've flown my -6 for almost 14 years and 98% of that time with a passenger. No problem. Now if we're talking the -4, manual flaps have a problem with the passenger's left foot, but on the sbs there's no problem.
Click to expand...

I like the way Sam Buchanan explained it. I guess if it's a skinny pilot & passenger, then it's no problem! :D

http://thervjournal.com/fuse7.html#flaps
 
No opinions

Too bad no one has an opinon. :eek: :rolleyes:

Just a data point the elect trim is lighter, that's all, trim sensitivity is not a real issue and you can add a device to slow it down at high speed and go fast at low speed.

http://www.aircraftextras.com/

(not a recommendation, just a data point)


http://www.rayallencompany.com/products/accessories.html

(you can install a switch, manual or on a micro on the flap to switch between slow and full speed, again not necessary but just info)

Manual flaps are fine but in my experience with a passenger (RV6 or RV4) its in the way. Also in the RV6 the last notch is a little awkward, just a little.

PS skip the top gun syndrome and forget the stick trim control or chinese hat, its in the way and can get hit accidentally. The trim toggle at finger tip postion with hand on throttle works well. The idea is one hand on stick other on throttle. The flap switch and trim (both elect) are next to throttle so hands can stay on controls and and eyes stay outside.
 
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My RV-4 has had manual trim from the start and it's always been a pain. That big slot machine handle to adjust it and that big cable to move a control that weighs a couple of ounces. I just recently ripped the manual trim out and put in electric trim. I am MUCH happier with it. Much easier to control. Plus the electric motor and the wire together weigh less than the old manual cable. My next RV will have electric trim from the start.
 
how about autopilots?

I see that autopilots are now offering the ability to control electric trim.... I was planning on manual trim but maybe this would be a good reason to tip the scales to automatic? Have any people with autopilots & manual trim wished for electric trim?

BTW - I built my trim tab for manual trim but I'm not above building another if I change to electric trim later...
 
IowaRV9Dreamer said:
I see that autopilots are now offering the ability to control electric trim.... I was planning on manual trim but maybe this would be a good reason to tip the scales to automatic? Have any people with autopilots & manual trim wished for electric trim?
Click to expand...

I think you're talking about 'trim sense' abilities of autopilots. They don't actually adjust the trim -- they will indicate (usually with an LED) that the plane is out of trim. The servo knows this if it is having to use a lot of force to keep the airplane in a level attitude. In this case, the trim sense will work fine with the manual or electric.

There was at one time an alt. hold on the market that used the electric elevator trim in place of an additional servo. Most RV folks that tried it said the elevator servo was too slow and the RV's too fast for it to maintain proper altitude.
 
flying with trim

I've gone electric, and I've flown both (manual in cessnas, and electric in Katanas). I LOVE electric trim. In my RV I want to have a control stick with buttons on the top of the stick for the trim, so I can use my thumb for trimming-out without even reaching for a trim switch.

However, I do caution that a too-convenient trim control can lead to a bad habit... flying with the trim. My instructor always emphasized that I should use the stick to put the aircraft into a stable configuration first, and then just trim to remove stick pressure. I still have to fight the lazy instinct to fly with the trim... for example I want to descend, so instead of pointing the nose down, letting it settle, and then trimming out, I get lazy and just hit the trim switch forward a few times and let the plane fly itself. With the manual trim I never did this, because reaching for the trim wheel required a conscious action.

Maybe this is just me, though. I'm still going with electric trim because, as was said before, this is to be a 21st century aircraft!
 
I think you're talking about 'trim sense' abilities of autopilots. They don't actually adjust the trim -- they will indicate (usually with an LED) that the plane is out of trim. The servo knows this if it is having to use a lot of force to keep the airplane in a level attitude. In this case, the trim sense will work fine with the manual or electric.
Click to expand...

The new pitch autopilots from Trio have an option that will actually adjust the electric trim and keep the plane properly trimmed while the servo is engaged. More info here:

http://www.trioavionics.com/alt_hold.htm

This is a feature I would want if my RV-6 had electric elevator trim, but after seven years of flying, I'm still completely happy with the manual trim.
 
pilot28906 said:
I have the tool kit from "plane tools" enroute and will be ordering the tail section for a 7A soon and see that manual or electric elevator trim has to be decided on early. I have flown mostly manual trim and wonder if the extra $ is worth it. Any opinions appreciated.

Thanks,
John
Click to expand...

John,

Something else to ponder, if you intend to fit a Fuel injection Pump from Vans Get the Longer RV8 manual trim cable for your 7, makes your life easier.

I decided initially to fit simple manual, but later decided on FI engine, found out cable too short if fitting FI Pump, Vans offered to swap cable, but me in South Africa shipping is going to kill me. Flown with a electric trim and liked it, so I ended up changing my mind, for easier install.

Regards
Rudi
 
I flown both

and they are both OK but the reason I don't like the manual trim is that is is placed in a similar locale to the prop and mixture knobs and looks/feels similar in the hand.

Just another critical knob to get confused when doing a high pressure TO/approach/landing at a busy airport...

Personal preference.

Frank
 
Electric Trim and Grips

After reading this entire thread I have one more question. I'm not too sold on electric aileron trim, mostly because of the extra money. However, I do have elec. elevator trim and have been looking for a grip that has provision for that trim plus PTT and a disconnect switch for the A/P. It seems everything I can find has a "coolie" switch and the options for more switches.
Any suggestions on where to look?
 
Pics

Would anyone have a picture handy of how the manual control looks in the cockpit of a 6/7/9 ? I browsed the virtual hangar but not so many pics of the interiors there.
 
PaulR said:
After reading this entire thread I have one more question. I'm not too sold on electric aileron trim, mostly because of the extra money. However, I do have elec. elevator trim and have been looking for a grip that has provision for that trim plus PTT and a disconnect switch for the A/P. It seems everything I can find has a "coolie" switch and the options for more switches.
Any suggestions on where to look?
Click to expand...

Like this?
Right_Grip_rt_rear_3-4_view.jpg

Look here->http://www.infinityaerospace.com/infgrip.htm
 
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