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Note the radial “stripes” on the intake lip. Never noticed it before, and I’ve never seen it on a model!
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Note the radial “stripes” on the intake lip. Never noticed it before, and I’ve never seen it on a model!
This is a very valued detail, Jennings! Thank you for sharing. Be patient…you WILL see those radial stripes…soon and very soon.
Paul
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Hello,
Interesting topic :GG, that looks to be N542KD. I noticed this a few years ago and thought it was a KLM only feature, specifically PH-KCD, but your photo certainly proves it exists on other operator MD-11.
They look like reinforcement “beauty” strips as they stand proud of the intake ring :
I am a big fan of all widebodies but the MD-11 is one airliner that will never cease to amaze me :love.
Cheers, Stephane
Cheers,
StefanProbably always there, just requires the right light to highlight it
https://www.airlinercafe.com/page.php?id=103
Can be seen in the parts that are in the shade more easily
Graeme
Greetings!
Yes, it is there, and I would bet on all 200 of them from the factory. It’s just a challenge to discern under certain lighting.
Regards,
Jeff Jarvis
God's "Curse" to aviation!
Greetings!
Yes, you’re quite right Stephane. That makes for a bit of a mystery. Is it a repair, or a modification, and for what reason? Since a local company has a large fleet of them, with both GE and P&W types of engines, I’ll ask some people who might be able to shed some light on it.
BTW, that local company just bought a few more, and they include the last one built, so you can guess where they are coming from….
Best regards,
Jeff Jarvis
God's "Curse" to aviation!
Even if they are repairs or doublers, it doesn’t make sense to me as I don’t think that part of the tail is under high stress. Or is it?
Thanks,
ahmed
KSFONo more stress than any other leading edge. Ever see them present on the wing mounted plants?
It’ll be interesting to hear what Jeff comes up with.>>Even if they are repairs or doublers, it doesn’t make sense to me as I don’t think that part of the tail is under high stress. Or is it?<<
Alan Aronoff
Where there's a will, there's a relative.Greetings!
Nothing specific yet, but he’s going to look into it. It may be a day or two, but I hope to be able to give you something definitive shortly. That whole area around the center engine intake with all the circular access cutouts looks very busy compared to engines one and three doesn’t it? I honestly have no clue why that stuff is there. Personally, the patches on the KLM bird (KLM 1, KLM 2) look like simple repairs, but the “Striped” radial strips do not. To me those look more like modifications, but for what purpose?
Best regards,
Jeff Jarvis
God's "Curse" to aviation!
PH-KCD
The plot thickens. Can’t see any other KLMs with this mod. Maybe a replacement/no genuine part but needed updating with additional strengthening to meet regs.
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Greetings!
Well, we have an answer, and just in time too! My friend is retiring this coming Saturday, so he will soon no longer have access to this kind of technical info.
The original intake ring was in 180 (or 90) degree sections, thus each section was quite large, very heavy and unwieldy. If you suffered a birdstrike from a large bird or a large piece of ice struck the intake ring, you would be screwed if the damaged aircraft landed at a station without heavy maintenance capability. You need cranes to lift those sections off the airplane, and it could easily take a couple of days or more to remove the damaged piece (s) and replace them, so MickeyD came up with an alternative intake ring with the straps being doublers covering the joints in more sections which are much smaller, lighter and easier to change out with just using a cherry picker, no cranes needed. The job can be done within a few hours thus greatly reducing downtime. Now, our former (for me, soon to be former for him) employer has not bought this modification because they have not felt a need, but you may recall that KLM had very high utilization daily on their MD-11 fleet and so this modification was of great benefit for them, and in fact they might have been the impetus to get MD to develop it. It is cheaper for several reasons. First, downtime is a fraction of what it would be with the two (or four) piece intake ring, and then you are replacing smaller pieces instead of big ones, so the pieces of hardware are less expensive, and the maintenance cost is much lower because mechanics (ground engineers) can do the job much quicker with less equipment.
Those circular access panels are mainly there to facilitate riveting. When you need to rivet inside the center intake tunnel, the access panels come off and the guy (or gal) who is doing the bucking has access to the back side of the rivet. I’m glad I flew (broke) them instead of working (fixing pilot breakage) on them because I’m deathly afraid of heights!
So, it is a modification and not a repair, but it was developed so as to facilitate repairs to reduce time and cost.
The Mighty Dog is quite an airplane, very quiet in the cockpit and it would undoubtedly have been a worldbeater with longer wings (A la DC-8-62/-63) as the engineers wanted to do*, but with all the stories circulating around about how squirrely it was, I wanted no part of it. I knew several guys who swore to me that there was no way they would ever fly it, but then the 747 Classic was replaced by the 747-400 which was domiciled in ANC only, and they wanted to stay international long haul but would not move or commute to ANC, so they went to the MD-11 after all. After several years I was at a retirement party for another pilot and every one of those guys told me that they wound up liking it after all, and it was actually a pretty good airplane and not as squirrely as they had expected. Some of that is due to the software that each company chooses for their fleet. Yes, they do vary… However, unlike MCAS, pilots are told about the software, at least, for the most part, they are in ground school! Another thing they told me was that the reliability of the airplane was very good, which was something of a surprise because in the beginning it was thought to be a dog, and not a mighty one at that. A friend who flew it at FedEx also told me that in his experience the reliability was quite good. Perhaps the MD-11 was not so deserving of my skepticism after all. Every time I jumpseated on one, if we departed late, it was never the airplane, but the loading being late.
Best regards,
Jeff Jarvis*The plan was for longer wings to improve cruise efficiency, but the factory would have needed expensive modifications on the doors to get the airplanes out. St. Louis told them no, you make it work with the DC-10-30 wingspan with winglets, and it could not be worked out with the shortfall in engine performance. Later on after tweaking the airframe and the engine improvements that were achieved, they got the performance that had been guaranteed and then some, but it was too late. The ETOPS for twins had killed three and four engine jets over water.
God's "Curse" to aviation!
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