Normally I try to not mention specific add-ons when talking about problems; it’s not fair to the add-on maker, it’s really hard to know what the real problem is without knowing everything about the bug, the problems I blog about usually affect a wide array of add-ons, and I don’t want to throw add-on makers under the bus. It’s not fair to them, particularly in this case.

In this case, however, approximately everybody knows that the Zibo was missing its wings in 11.50 beta 9 – it’s a very widely used add-on, and it’s a perfect illustration of the problems with third party content validation, which is what this post is about.

So…gather round children, and I will tell you the tale of how the Zibo lost its wings.

We Added New Error Checking to the OBJ Loader

Sidney and I have been going through X-Plane 11.50 crashes with a fine tooth comb, and one category that stuck out were crashes when loading and drawing OBJs. From what we could tell, the crashes were happening because the OBJs themselves had bad data in them.

The problem with this kind of crash is that X-Plane just crashes and asks you to report the problem to us; it doesn’t tell anyone which object has the problem, which means the scenery authors can never fix the problem.

So in X-Plane 11.50 beta 9, I added validation checks. They catch every case where invalid OBJ data could cause the sim to crash, they report the error, and the object is effectively removed so it can’t crash the sim.

Some Errors are Really Bad, Some Less So

Here’s the problem: the errors we are detecting can crash the sim. But they don’t always crash the sim. It depends on the particular invalid data.

We put the error checks in to find specific crashing objects, we found them, and we notified the authors. But now that we have complete checking, aircraft that have OBJs that violate the OBJ spec (but happen to work with X-Plane 11.41) are now kicking up warnings.

Thus, the Zibo. The wing object has what I can only imagine is a copy-paste error, and by good fortune, it happens to be harmless in X-Plane 11.41. But X-Plane 11.50b9 is a stickler now, so the wings don’t get loaded because they contain an error that could, in theory, crash the sim.

Beta 10 Will Be (Slightly) Less Cranky

X-Plane 11.50 beta 10 relaxes the really heavy error checking on a small number of cases where X-Plane 11.41 would not complain and we were able to determine that the sim would not crash; these errors will still be logged and authors should still fix them. In the case of the Zibo, this change will bring the wings back (although I understand that the authors fixed the problem very rapidly).

We have seen some high profile OBJ problems that we cannot work around; the OBJs are simply too weird. In these cases the OBJ ends up missing, so we still will have the loud squawky message in X-Plane 11.50 beta 10.

About Ben Supnik

Ben is a software engineer who works on X-Plane; he spends most of his days drinking coffee and swearing at the computer -- sometimes at the same time.

16 comments on “How The Zibo Lost Its Wings

  1. Hi Ben !
    Is there a little chance we see Beta 10 this weekend ?
    We have rainweather in europe 🙂

      1. 🙂 hmmm… feels like christmas … let’s update.

        First impression:
        PEOPLE: This beta 10 is awesome. Even faster, supersharp textures. I love it …

  2. Makes sense Ben. Thanks for clarifying the ‘James Bond’ wings 🙂 Keep up the nice work.

  3. Hi there

    With XP11.50b9 I also had the missing wings issue with Zibo 737-800X version 3.4. However, having experienced this, I then installed the latest Zibo 737-800X version 3.42 and the problem had been solved, in other words, Zibo had already found a solution themselves 🙂

  4. Is there any working zibo 737 700 or 800 that works with Beta-9 or is everything working in Beta-10? I’m confused. Sorry

  5. Thank goodness. When the error message appears in the log about the wings object being potentially corrupt, I was wandering if my 10 year old hard disk was on its last legs.

    A checkdisk scan however revealed no errors. I was somewhat confused by the fact that I could actually delete the wings.obj file. Normally I find that corrupt files have to be fixed using the checkdisk tool before I remove them.

    I think that nice new solid state M.2 drive can wait in my shopping basket a little longer. Thanks for the blog post.

  6. Hello, i have updated to beta10 and ever since my sim starting to stutter a lot, frames dropping and increasing all the time. I have removed all the adon plugins i use but it still the same. I have tried reverting back to beta9 but it seems that’s not possible. Will appreciate it if you could help in solving that issue.
    Thanks a lot

  7. I also happened to be flying the Carenado T210 Centurion with the Reality Expansion Pack and noticed in 11.50 the RPM, Airspeed Indicator, Gyro, Artificial Horizon, Standby Horizon all stopped working. They worked on .41

    1. One minute I am able to load the sim and do a flight out of KJFK without any problems. The following day I tried doing the same exact thing except this time the game wont load the flight at all.

  8. The progress and support for these betas is nothing short of fantastic however like in this case the beta left me unable to fly my favourite plane!( until it was fixed a couple of days later). I think it would be great if we could downgrade to certain betas during this period instead of the only option being going back to 11.41. I can’t go back now I have seen what a difference 11.50 makes .

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