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RV-9A vs RV-7A for a newbie?

scannis495

I'm New Here
I have been looking from afar for a while and now am ready to get more serious about an RV, and would like some advise.
Background-I'm 63 years old. I have 2,300 hours in Cessna's- 172, 182 & 206. I fly surveying in a 206 and have 600 hours this past year. I'm ready to semi-retire and would LOVE to build an RV14. I just sold my 172 and am looking for a 9a or 7a to tide me over until I build the 14.
I have several questions and would love some experienced input.
The flying I expect to do is mainly cross country flights from 100-1,000 miles. I wouldn't fly hard IMC but don't usually let weather stop me. I think I would mostly be flying at 75% horsepower and think the bigger engines, constant speed prop, available in the 7 would be a better fit. I'm wondering if the wing in the 9 would be more suitable for my mission? Having never flown a nimble machine, is one easier, more forgiving for a newbie than the other? Also I can get a hanger at an airstrip with a grass and rough/poor asphalt strip; would that be an absolute red light.
Thank you in advance for your help!
 
It sounds like they'll both work just fine for you. As you're buying, I would think you'll be perfectly happy with a nice example of either that you find within your price point.
 
Welcome to VAF

Steven, welcome aboard the good ship VAF:D

The fuse is virtually identical for the 7 and 9. big differences are the wing, and the 9 is not aerobatic.

The Vans factory folks seem to like the 9 for cross country work.
 
9 if you want fuel efficiency, 7 if you want to fly upside down and have a little more power (burn more fuel).
 
All RV-9A and -7A built up until about 4Q2019 will have a simple solid nose gear leg with a castoring wheel. Many people fly with this gear from (somewhat) rough or grass strips without problems. But the leg is unforgiving of pilot error and/or chuck holes and there have been a number of "pole vault" flips as a result. From 4Q2019, Vans has offered a sprung (with rubber biscuits) tubular nose gear similar to the RV-10 and RV-14. This is available as a retrofit kit, but unfortunately also requires a new engine mount.

Vlad on the forums here has flown his aircraft to numerous rough or grass strips without problems.

Anti-Splat Aviation offers a nose gear leg strengthening kit "The Nose Job"

Just a caution, you should evaluate how "rough" the strip you intend to use is.
 
The grass field is not real "back country rough", really not bad. The asphalt runway has weeds growing through and loose gravel. Thank you for the info.
 
The flying I expect to do is mainly cross country flights from 100-1,000 miles. I wouldn't fly hard IMC but don't usually let weather stop me. I think I would mostly be flying at 75% horsepower and think the bigger engines, constant speed prop, available in the 7 would be a better fit. I'm wondering if the wing in the 9 would be more suitable for my mission? Having never flown a nimble machine, is one easier, more forgiving for a newbie than the other? Also I can get a hanger at an airstrip with a grass and rough/poor asphalt strip; would that be an absolute red light.

* As previously mentioned, the -9 is generally regarded as a better cross country machine because it is a bit more stable than the aerobatic -7
* The -9 is not good at cruise speed in cumulus clouds because the light wing loading makes the ride very bumpy. I slow down to 100 knots in cumulus clouds for that reason
* The -7 should be somewhat better in bumps with higher wing loading, but still...
* In aforementioned cumulus clouds, the -9 will easily get bumped into 30° banks, pitch excursions, etc. I expect the -7 to be worse. Nothing like the 206...
* In this age of autopilots, some of this is a so what -- as long as the autopilot is working properly. Some autopilots can have steep learning curves, especially in a mixed vendor system
* Cruise speed difference between the -7 and -9 is a handful of per cent, not enough to drive the decision
* Definitely want a constant speed prop. No tradeoff between climb and cruise, more descent capability and drag on landing, but most especially, don't need to be fussing with the throttle in up and down drafts
* Grass is doable, but good technique is essential. Anti-splat nose gear add-on recommended
* The -9 will be an easier transition, but both will require a transition. The -7 will probably develop a high sink rate on final if slow, more than the -9
* Nosewheel recommended for practicality, especially if it's a gusty crosswind after a long, bouncy flight.

Personally, I'd recommend the -9, but would not recommend against the -7

Ed
 
Another vote for a 9A as a cross country machine. I had similar wish list about 6 years ago and weighed the same question....7 or 9. I was open to either when looking for a potential purchase and found a 9. Now have 600 hours (about 50% of which is 200+ mile cross country flights) and am extremely pleased with it. The 9 loves to fly high. Depending on the flight distance, I will often fly between 12-16K (with oxygen) and the plane performs beautifully.

Best of luck with your search!

Mike
 
Careful with that 9A - you'll find out you like it so much you'll give up the idea of building a 14! :D
 
Quick side question...

* Definitely want a constant speed prop. No tradeoff between climb and cruise, more descent capability and drag on landing, but most especially, don't need to be fussing with the throttle in up and down drafts

I've got a constant speed prop, but still find that I sometimes have to adjust the throttle in up and down drafts. Is there a technique missing from my toolbox?

Also, agree that the difference between a 7 and a 9 is not as important as striking fast when you find a good used 7 or 9.
 
I've got a constant speed prop, but still find that I sometimes have to adjust the throttle in up and down drafts. Is there a technique missing from my toolbox?

Also, agree that the difference between a 7 and a 9 is not as important as striking fast when you find a good used 7 or 9.

Maybe you need a new governor - it should not need adjusting with the throttle at all to maintain RPM.
 
I've got a constant speed prop, but still find that I sometimes have to adjust the throttle in up and down drafts. Is there a technique missing from my toolbox?

9.

I think Ed meant that in all but the worst cases, a CS prop gives you the option to maintain altitude with elevator only, accepting airspeed changes. With a fixed pitch prop you may need to reduce throttle in downdrafts, to avoid going over the rpm red line.
 
Ah. Right.

I think Ed meant that in all but the worst cases, a CS prop gives you the option to maintain altitude with elevator only, accepting airspeed changes. With a fixed pitch prop you may need to reduce throttle in downdrafts, to avoid going over the rpm red line.

Okay, I get it now. I sometimes need to reduce throttle in downdrafts to avoid going too fast, but the RPM stays where it is supposed to.

I'm finding, when punching through summer cumulus, that it's often wise to just slow the thing down generally. Makes Mr. Toad's Wild Ride a bit less wild. Even at slower speeds, holding a given altitude in cumulus in a -9 without an autopilot requires.... sustained attention. Not sure if a -7 is noticeably different?
 
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