Viking Engine

[fastj22]

Funny really ...

When he was trying to sell it on Barnstormers there was no mention of any of this. I also wonder if he realizes that on his web site in his own words he says of this exact airplane, "Viking Waiex - 160 mph cruise and a BLAST to fly." That quote and the photo of the plane is here (1/2 way down the page):

http://www.vikingaircraftengines.com/sonex.htm

So he was either lying then or now ...

Dale
N319WF

I have flown my Jabiru powered Waiex (10 more HP than the Viking) at 160MPH (TAS) cruise and will confirm its a BLAST to fly. No lie there. No need to adjust the wing incidence, nor the tail. In fact, its amazingly hands off at that speed.

Perhaps, Jan should consult with Kerry or Jeremy before re-rigging his wings and adjusting the tail. Or read the NTSB report on the deadly Waiex incident. That's a very significant mod to the design and should probably get a professional engineer to review it. Seems to me to be a thrust vector problem. Either the Viking plane was built twisted, or his engine mount isn't appropriate for the airframe.

I sure hope he's done the tail SB. Wouldn't want that tail shaking off at those incredible speeds the Viking delivers. Seconds to cruise speed is very impressive. Must really throw you back in the seat.

[Don Bowen]

I think the problem here is specific to the Waiex in question. Something about this airframe is out of conformance to plans. The Jab 3300 powered Waiex will fly just as fast and does not encounter these issues. The Corvair 'Cleanex" aircraft are just as heavy or heavier than the Viking conversions and don't exhibit this type of trim problem. I don't believe it is necessary to change the angle of incidence of the wings or tail. It could be the plane was built out of rig or the trim system is not installed correctly or doesn't have the correct springs installed. I believe whatever the problem is it is specific to this airframe and not indicative of any general problems with the Waiex design or the choice to equip it with a Viking engine. As others have said, I hope Jan has complied with SB #1. It is a pain to do, but safety demands it.

Last I spoke with Ken Robbers (about a month ago) he had over 230 hours on his Viking Sonex and he seems quite happy with the airframe and engine combination. I am sure if anything drastic like this was going on he would have mentioned it.

I always liked the way my Waiex flew, but I never had much luck with the AeroVee engine. Not slamming the AeroVee, I know lots of people have success with them but my AeroVee was very problematic. Going to the Viking has increased my empty weight by about 30 pounds. The batteries are going in the tail to keep the CG within limits. I should be flying again by late spring or early summer.

Whether or not you like Jan and/or the Viking engine, I think there is something wrong with this aircraft, not the Sonex/Waiex Viking combination.

Just my opinions. Happy flying to you whatever engine you choose.

Don Bowen
N49YX
KMCC

[fastj22]

Got to thinking about changing the wing incidence on an already rigged airplane. If only moving the rear spar measurement, that would put twist strain on the main wing bolts and spar. So the proper method would be to replace the entire spar box and fuselage supports along with the rear spar carry through and re-drill for the bolts to the new alignment. This is not minor, but a huge undertaking.

[rizzz]

Whether or not you like Jan and/or the Viking engine, I think there is something wrong with this aircraft, not the Sonex/Waiex Viking combination.

It is clear something was wrong with that Waiex from the beginning, and it is certainly not a case of “too much power” as jab would like to make us believe.
I found it very suspicious he put the airplane on Barnstormers immediately after completing his Viking installation and no picture or anything of the aircraft actually in flight. He was very quiet about it on his forum and website as well, he just tried to make it disappear.

It is also very clear is that Jan is not honest about what exactly is the issue with this plane.
It is not the Viking I don't like, it is Jan I don't like, he proves again and again you can't believe a word he says.

BTW,
Does anybody know the history of this Waiex?
I can't quite read the registration from the picture on his website.
Would be good to know whether it had any issues flying with the original AeroVee engine.

[daleandee]

BTW, Does anybody know the history of this Waiex? I can't quite read the registration from the picture on his website.
Would be good to know whether it had any issues flying with the original AeroVee engine.

Start here:

http://registry.faa.gov/aircraftinquiry ... ertxt=65yx

Then follow it to here:

http://www.wysk.com/index/florida/edgew ... lc/profile

Then click the "officers and directors tab":

http://www.wysk.com/index/florida/edgew ... c/officers

and then click on Jan's name:

http://www.wysk.com/search/doEntitySear ... GENFELLNER

This confirms the tail number of N65YX and that it was Aerovee powered.

Take that to the Sonex site:

AAArrrrrhhhh ... I cannot get a link to work but search builders under Waiex serial number 65.

A search of the NTSB database for "Waiex" model show 5 accidents and none with that tail number. Sonex shows the builder as Shayne McDaniel and the current owner as Jack Nelson. The FAA registration does show the new owner as pending but I thought it said that back when it was on Barnstormers. But in reality all of this really says nothing at all.

Jan may want to contact the FAA before he takes off in that airplane again as the FAA data base puts up a warning before you get to the registration that reads; "This aircraft's registration status may not be suitable for operation."

FWIW,

Dale
N319WF

[rizzz]

BTW, Does anybody know the history of this Waiex? I can't quite read the registration from the picture on his website.
Would be good to know whether it had any issues flying with the original AeroVee engine.

Start here:

http://registry.faa.gov/aircraftinquiry ... ertxt=65yx

Then follow it to here:

http://www.wysk.com/index/florida/edgew ... lc/profile

Then click the "officers and directors tab":

http://www.wysk.com/index/florida/edgew ... c/officers

and then click on Jan's name:

http://www.wysk.com/search/doEntitySear ... GENFELLNER

This confirms the tail number of N65YX and that it was Aerovee powered.

Take that to the Sonex site:

AAArrrrrhhhh ... I cannot get a link to work but search builders under Waiex serial number 65.

A search of the NTSB database for "Waiex" model show 5 accidents and none with that tail number. Sonex shows the builder as Shayne McDaniel and the current owner as Jack Nelson. The FAA registration does show the new owner as pending but I thought it said that back when it was on Barnstormers. But in reality all of this really says nothing at all.

Jan may want to contact the FAA before he takes off in that airplane again as the FAA data base puts up a warning before you get to the registration that reads; "This aircraft's registration status may not be suitable for operation."

FWIW,

Dale
N319WF

Thanks,
At least it looks like N65YX was at least flying with the AeroVee:
http://www.sportpilot.org/magazine/feat ... Flying.pdf

[rizzz]

Got to thinking about changing the wing incidence on an already rigged airplane. If only moving the rear spar measurement, that would put twist strain on the main wing bolts and spar. So the proper method would be to replace the entire spar box and fuselage supports along with the rear spar carry through and re-drill for the bolts to the new alignment. This is not minor, but a huge undertaking.

If you read his last post on the issue (I quoted it on the previous page in this thread), he claims he's already done this change and it did not help enough.
Given that re-rigging the wings properly (some of us on this forum have had to do it) takes months, I would suggest that IF what he claims is true he has not worried about replacing the spar box & fuselage angles which would mean he now has an airplane with twisted main spars.
IF this is indeed true I hope he won't try to sell this airplane again.

[tonyr]

Got to thinking about changing the wing incidence on an already rigged airplane. If only moving the rear spar measurement, that would put twist strain on the main wing bolts and spar. So the proper method would be to replace the entire spar box and fuselage supports along with the rear spar carry through and re-drill for the bolts to the new alignment. This is not minor, but a huge undertaking.

I dunno if the twisting effect at the spar is going to be that much, he changed the position at the rear spar by .156" , the main spar is 19" away.. is that a significant twisting moment at the bolt hole? I'd try and calculate the amount of twist but you guys are much smarter than me :) He probably pulled the rear bolts and let the spar drop the .156" (its natural resting position) then re-did the mounts.

I agree though its a bit stupid to change the wing rigging for a thrust and trim issue, when there are no other high horsepower airframes that we know of that exhibit the same problems.

Richo
#813 2200 Puny Power

[fastj22]

If you need to change the wing/tail incidence to remedy an engine swap problem, perhaps its not the wing/tail incidence but the engine/mount that's the issue. I have heard of no Sonex/Waiex/Onex/Xenos that required a deviation from the factory wing rigging parameters to balance the plane properly. All flying Waiex with the same or more HP (Jab, Corvair, Rotax) than the VIking do not have this problem. Something is very wrong with this Viking Waiex. I doubt its the Waiex part.

[rizzz]

The discussion is continuing on the (official) Viking group:

I think this is a trim thing not balance because tried putting 8 pounds on lead on the tail wheel it had no effect at all my sonex dose have the same issues

http://groups.yahoo.com/neo/groups/Viki ... sages/4747

Opinion. You are probably producing near Jabiru power, maybe a little more. I have not heard of Jab Waiex'es with such control issues.

This aircraft was not built by you. It just doesn't sound like this airframe is right....and if it is not, it is probably in the tail.

Or, very aft CG.

It certainly wouldn't take much.

http://groups.yahoo.com/neo/groups/Viki ... sages/4748

I am curious about this. You are running about the same speeds as the Jab 3300 powered planes, but they don't seem to be reporting this issue. Can you trim it out? Or are you changing the angle of engine mount or wing incidence? Is this as serious as Jan makes it sound or is it something that can be lived with. Just trying to figure out what is ahead of me with this project.

http://groups.yahoo.com/neo/groups/Viki ... sages/4749

No its not a big deal just trying to make it better my plane flys hands off a crus you beed ruder input with power above 5,000 rpm or below 3200 its just could be better i hear other sonex air craft can't take thier hands off so i think my sonex flys grate just would like 2 deg left trust that way i would not need left ruder on take off and right ruder in descent

http://groups.yahoo.com/neo/groups/Viki ... sages/4749

Well, you can't live with the airplane climbing when you want to stay level. So you do need enough trim to hold it level.

You can have this if you increase the forward spring force, but it will proportionately lessen the amount available for up trim when flying slow.

So, you end up holding the stick back during the entire approach and landing.

The system is not capable of trimming the speed range from 40-170mph

This might have to do with:

- The large flyable speed range
- Inherent to the type of airfoil
- The V-tail being less powerful, hence the trim less powerful
- The trim system is inadequate for the job (not enough range

I have now added two external tabs to the airplane, one on each ruddervator. However, I believe a more powerful spring system would have less drag

Viking

http://groups.yahoo.com/neo/groups/Viki ... sages/4750

Yes stronger springs on the trim would deftly help im going to do that !!!!

http://groups.yahoo.com/neo/groups/Viki ... sages/4751

If I understand Ken's posts correctly, he's saying there is a similar problem on his airplane but it's not such a big deal on his Sonex and he's able to cruise level hands-off.
(it's really hard to read his posts, I think he uses some sort of speech recognition tool to write his posts).