Visibility on the 7 vs. the 6

[Darren S]

Hi group,

Please educate a newbie and help me make a decision. I would really like to know the big differences between the -6 and the -7. I know the vertical stab is much larger but other than that, can those who know tell me some more.

Also, is the visibility better on the -7 or is the same as the -6 ?

Hope to join the family soon,

Thanks,

Darren

 

[hecilopter]

Several subtle differences

More fuel (42 vs 38) = greater range, longer wingspan (a foot or so), larger tail, counter balanced rudder, thicker emp. skins (to accomodate 200hp), higher Vne (230 vs 210), higher gross weight are a few I can think of.... can't comment on the vis for a -6 or -7 since I have a -7A, which has excellent vis on ground and in flight...

 

[Jamie]

The Van's website is a pretty good source of info. Read the specifications and it will give you pretty much all you need to know.

The internal dimensions of the -7 are also different. IMHO the -7 has more room in it than the -6. It's a minor amount, but it's noticeable enough for folks that have any time in both airplanes.

The -7 has more:

Wing span (two feet)
Fuel capacity (four gallons)
Leg room (barely, but it is noticeable).
Engine options (if built to plans, the -7 can use a 200hp IO-360).
Useful load. The -7's gross weight is higher.

Again, check out Van's site for the specifications on both models and you can do a SBS comparison.

And for the visibility question....there's really not a difference at all. All things considered the airplanes are pretty darn close to each other. The -6 does have a completely different spar/carry-through design.

 

[Mel]

The internal dimensions of the -7 are also different. IMHO the -7 has more room in it than the -6. It's a minor amount, but it's noticeable enough for folks that have any time in both airplanes.

The cockpit widths are the same. The -7 has more head and leg room.

 

[N941WR]

The -7 is stronger than the -6

The visibility out of the -6 & -7 are about the same.

In addition to the increased dimensions of the -7 the acro GW went up from 1375 lbs for the -6 to 1600 lbs for the -7 & -8. Note, earlier -8's with the original wing have an acro GW of 1550 lbs.

Those weights give them a +6/-3 G (plus 50% safety factor).

These numbers came from Section 15, AEROBATICS in the builder's manual, if anyone wants to look them up.

(FYI - The -9 can withstand utility design loads of +4/-1.8 G at a utility GW of 1600 lbs.)

 

[David-aviator]

When I ordered the 7, one of it's features over the 6 at that time was better visibility. This was accomplished by lowering the engine about 1 inch. The top cowl slopes down just a bit more improving forward visibility.

 

[flion]

It may be a moot point. Unless you are planning to buy at least a partially completed -6/6A, you have no choice. (Yes, I know, there are ways around this, but not practically.) Since the -7 is the replacement design for the -6, Van's no longer offers empennage kits for the -6 and, if you were starting from scratch, you have to go with a -7 (or -9).

If, on the other hand, you are looking at two completed (or nearly so) aircraft, they will be so similar that the slight differences will probably be outweighed by the installed equipment. I had the impression you were planning to build but nothing in your post backs that impression up.

Finally, visibility. The big visibility difference in the side-by-side models is tip-up versus slider, not model. The rollbar/targa strip in a slider is definitely in your field of view but it is not much of a factor for visibility. The rollbar/targa strip for a tipup is only in your view when you crane your neck around to see behind you, is more substantial than the slider but due to the position I find it also not much of a factor. I'm sure I've just ignited the wars again, even though my personal opinion is that it's all good and just a matter of personal preference. There are other considerations re: tip-up versus slider that have nothing to do with visibility but you can read about them (and others should comment on them) in the already existing threads on this debate.

 

[JonJay]

Slightly

I have flown both. The 7 is slightly better visibility wise and feels roomier even though the dimmensions for width are the same. I will argue that the 6 spar is the strongest in the fleet, but I think the aerobatic gross weight issue is a hold over from a more conservative time.

 

[Darren S]

Thanks for the great replies and help. I am leaning towards the QB -7 but am a little nervous about the magnitude. I have built a Challenger Ultralight in the past and a Sonex , but still a little timid I guess. Also the wait times for a QB kit is something like 6-8 months ??!! That's long.

Anyways, let me stir the pot a bit more. I like a little bit of aerobatics. Like the stuff seen on Youtube. Half Cuban, point rolls, hammerheads etc..... Is the -7 as "nimble" as the -6 ? For those whom have flown both ?

Thanks again for the replies

Darren

 

[yakdriver]

The 7 cockpit is 13/4" deeper than the 6 from the floor to the canopy rail at the spar. The instrument panel is also about 11/2" forward than the 6. The canopy on the 7 is about an inch higher. Doesn't sound like a lot but makes for a much roomier cockpit. I fly my 7 and a friend's 6 quite often and there is not much difference in control feel and response. Don

 

[az_gila]

Some (most?) of the wing...

.....The -7 has more:

Wing span (two feet)
......

...span difference is in the fiberglass "bat" wing tips that can be retro-fitted to a -6 model.

Or, I guess a -7 can be "shortened" by using old style -6 wing tips...

 

[nucleus]

...span difference is in the fiberglass "bat" wing tips that can be retro-fitted to a -6 model.

Or, I guess a -7 can be "shortened" by using old style -6 wing tips...

I don't think so Gil, there is a two foot difference in wingspan, 23 vs. 25 feet. The new wingtips are not a foot longer on each side.

Hans

 

[yakdriver]

Hans, The only difference on wingspan is the tips. I have had a 6 and 7 sitting side by side when I took all the cockpit and wingspan measurements. Don

 

[JonJay]

Teh 6 rolls a little quicker

Thanks for the great replies and help. I am leaning towards the QB -7 but am a little nervous about the magnitude. I have built a Challenger Ultralight in the past and a Sonex , but still a little timid I guess. Also the wait times for a QB kit is something like 6-8 months ??!! That's long.

Anyways, let me stir the pot a bit more. I like a little bit of aerobatics. Like the stuff seen on Youtube. Half Cuban, point rolls, hammerheads etc..... Is the -7 as "nimble" as the -6 ? For those whom have flown both ?

Thanks again for the replies

Darren

...but the control feel is very similar.
I know you want to build, but there are some smoking good deals on used 6's right now. For the prices I have seen, you could save thousands buying used over building, just in parts costs alone, let alone time.

 

[Sam Buchanan]

Thanks for the great replies and help. I am leaning towards the QB -7 but am a little nervous about the magnitude. I have built a Challenger Ultralight in the past and a Sonex , but still a little timid I guess. Also the wait times for a QB kit is something like 6-8 months ??!! That's long.

Why a QB? In the 6-8 month window your stated you could build standard sub-kits and keep several thousand dollars in your pocket.

The tedious part of the project is not the airframe but the panel, systems and finish. That is all the same whether quick or standard-build.

You have the technical background to build an RV, you just need to decide if you are suited to a 2-4 year project.

 

[chaskuss]

6 & 7 use differing wing spar designs

Hans, The only difference on wingspan is the tips. I have had a 6 and 7 sitting side by side when I took all the cockpit and wingspan measurements. Don

Don & Gil,
I find it hard to believe that you are both correct. The 7 and 7A use the same wing as the RV8 and 8A. (24 foot span on the 8, 25 foot span on the 7. The extra foot of span on the 7 may be accounted for by the Bat Wing tips? Vans has redesigned the tips for the 7 and 8. The RV8 originally used the old Horner wing tip design. (same as the RV4 & 6) The newest RV7 & 8 wing tip design no longer have bat wing flare at the rear. The 6 uses the same wing design as the RV4 (23 foot span)
Wing area on the 6 is only 110 square feet. The RV8 has 116 square feet and the 7 has 121 square feet of wing area. I just verified all this info on Vans web site.
One more item that differentiates the 7A from the 6A is the wing spar design. The older 3, 4 & 6 wing main spars are of a two piece design. The spars went into sockets in the fuselage. They touched each other. The newer 7 & 8 style spar is a 3 piece design.
This becomes an issue with the tricycle gear versions of this design, as the main gear sockets attach to the wing spars. With the older spar design, removal of the wings will require removal of the landing gear and main gear sockets. This is NOT a trivial amount of work.
With the newer 3 piece spar design, only the bolts which secure the center section of the spar to the outer sections need to be removed. The 9A also uses the newer, 3 piece spar design.
Charlie Kuss

 

[rvbuilder2002]

The RV-7 uses the RV-8 wing which has a wing panel that is longer than an RV-6 (same 23' span but with a anrrower fuselage).
When you put an RV-8 wing (longer wing panel) on an RV-7 side by side fuselage you end up with a wnig span that is slightly longer than that of an RV-6.

 

[Darren S]

parts availability for -6's

Wow, what terrific information. Thanks everyone. I like JonJay's suggestion about picking up a used -6. The prices are very tempting and it would allow me to scratch my building itch while keeping the finish line in sight.

Can I get some comments/opinions on how difficult parts for a -6 will be in the next 5-8 years. I feel a little uncomfortable buying an "outdated" model (please don't take that the wrong way you -6 builders) but does anyone have the inside scoop on when Van's will cease making parts for a -6 ?

Thanks all.

Darren

 

[jsharkey]

Wow, what terrific information. Thanks everyone. I like JonJay's suggestion about picking up a used -6. The prices are very tempting and it would allow me to scratch my building itch while keeping the finish line in sight.

Can I get some comments/opinions on how difficult parts for a -6 will be in the next 5-8 years. I feel a little uncomfortable buying an "outdated" model (please don't take that the wrong way you -6 builders) but does anyone have the inside scoop on when Van's will cease making parts for a -6 ?

Thanks all.

Darren

I don't have any inside information but I'd assume based on my experience so far that Van's will keep making and selling -6 piece parts for as long as anyone wants to buy them. Not so sure about QBs though.

Jim Sharkey
RV6 - Awaiting Certification Paper Work from FAA

 

[JonJay]

Not an issue

Wow, what terrific information. Thanks everyone. I like JonJay's suggestion about picking up a used -6. The prices are very tempting and it would allow me to scratch my building itch while keeping the finish line in sight.

Can I get some comments/opinions on how difficult parts for a -6 will be in the next 5-8 years. I feel a little uncomfortable buying an "outdated" model (please don't take that the wrong way you -6 builders) but does anyone have the inside scoop on when Van's will cease making parts for a -6 ?

Thanks all.

Darren

Van's no longer supports the empennage(but the 7 can be made to work). However, there are hundreds of unfinished 6 kits out there that will never be finished. You see them advertised all the time. There will be parts available on the market for many, many years. Even if you could not find a specific part, everything in the kit can be built from the plans.
If you buy a flying airplane, you will set back your build. You need to decide what you want to do. 4's and 6's are way undervalued right now so it is a buyers market.