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JayW

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JayW last won the day on February 12

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About JayW

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  • Birthday 06/05/1951

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  1. Man - I am sooo impressed with the wing skins Peter. Question - what are you going to do about the tires?
  2. "Man there's some work in those Jay!" True statement Craig! It is actually a fun project, and they are little models in themselves. You ain't seen nothin' yet. Lots and lots of work remaining. The challenge of course is to make them look crisp and not sloppy. Did I heat the nose pieces? No. The gage is .01 inch which is fairly formable as is. What I did do is to "pre-form" the pieces over small diameter tubing. Although there was alot of springback, from there it was fairly easy to wrap around the former ribs. Contour is not that severe, and the length of the part is nothing like a flap or aileron nose skin. BTW - I try to use styrene as my go-to material, because glue, either liquid or tube, is so effective. Metallic materials rely on epoxies, which do not weld the material together like styrene glue does, but just fill in micro pockets and other irregularities. So the bond often is not as robust. And, curing time is longer than a styrene glue bond. I have been burned before, however, and wished I had used something else!
  3. I have an "interim" report on the bomb pylons, or "wing tank adapters". Here is a repeat photo of this item: That way you can look at some of the details I am attempting to replicate and compare. This is difficult work to get right. My first effort was (is) to create the forward portion of the pylon box. It involves two side skins, a forward frame, a mid frame, and a bottom "floor" of sorts. The framework provides the shape the side skins must take, and also provides the mounting surface for the bomb shackle, and later the sway braces. It also provides the attachment surfaces for the aft end of the pylon which I have not started yet. Here is the basic forward box (both of them): The shackles are very similar to the centerline one I showed a couple of posts ago. You also see the side skins - notice the aft ends where contour transition begins. A very pesky thin bent-up "bulkhead" holds the local contour and forces it to taper to a sharp edge. This will be much more evident when I produce the aft portion of the pylon. A couple more shots: I have included the Dzus fasteners similar to what was done on the wing and fuselage, only smaller diameter. Note also the elliptical nose formers I have included in which to attach the nose skin shown here: Man - that little curved skin part is pressure packed. It is the most visible part of the pylon and it has to be good. This includes properly matching up to the wing contour. I fail on this part, and I have to start over. The part you see has excess on all four sides and is trimmed to shape after being glued to the nose formers. Like this: Here is a test fit: So far , so good. It was just a matter of filing and sanding a little at a time til it fit up OK. There is much to go. Complicated little suckers these are!
  4. DeanKB says this: "Criticising dead aircrew, before any investigation, whilst rallying against people giving inaccurate reporting? Very distasteful." I certainly agree. Not time to place blame yet. There will probably be plenty to go around, including on BA. However I stand by my comments about news media (regardless of any political bias that may or may not exist) regularly botching anything that is technically complicated, and falling prey to the temptation to report in a sensational manner in the interest of retaining viewers or readers. Latest reporting is the Ethiopian crew followed the manufacturer's (and FAA's) procedures to mitigate such a MCAS anomaly. Sounds like that may have come from lawyers looking to maximize the settlement. I find that exceedingly hard to believe and think it will fall in the above described category. That is tantamount to BA basically committing suicide. Were it to be true that an AD (airworthiness directive) that addresses a fatal crash (Lion Air) would cause another crash (Ethiopian), that would likely be the end of Boeing, and a massive house cleaning at FAA. Hence my suspicions. I'll repeat - let's be patient.
  5. In my experience with the Seattle Times and Boeing (it's been quite a while), their technical people were guilty of a fair amount of "yellow journalism" over the years. I cannot speak for today, but their history of trying to rake their own biggest business (Boeing) over the coals is long and unethical. They wanted to sell newspapers at the expense of everything else. I speak from knowledge. A great example - in 1989 a 747 experienced a cargo door failure and subsequent explosive decompression while climbing out from Honolulu. Some of you may remember. This was an unfortunate incident that killed several folks, but the aircraft was returned to the airport (not without great difficulty and some pretty heroic action by the flight crew). The Seattle Times had a heyday with this incident, misrepresenting almost every story they wrote - at times intentionally, all to sensationalize the event and pillory Boeing for being corrupt and covering up critical information. They sold lots of newspapers. At the time I was the engineering supervisor of the pressurized door group on the 747 sustaining engineering program - so I was in a position to see up close what was being reported and compare to the facts. It was eye opening. All this to say, an airplane crash or incident is almost invariably technically complicated, and the news media in their haste to get the story out almost invariably gets key facts wrong. The above incident certainly was that way. I think we will find the latest reporting on the Ethiopian accident and turning off the MCAS, and other reporting on old 737 flight manual info that is not now present to have kernels of truth, but leading to incorrect conclusions. You can bet the NTSB, Boeing, and the FAA will get to the bottom of it. Let's be patient and see.
  6. Antonio - just absolutely amazing find!!! And Peter - the wing surfacing is perfection in the making. Makes an old P-51 fan proud. I also love the cast prop blades. I had to cast one for my P-47 - what an adventure that was!
  7. Continuing - I know for a fact that most if not all airplane programs have late crises that risk the program. The 747-400 had one where the increased engine thrust was found (very late) to render the rudder authority uncertifiable for engine out take-off performance and possibly some other requirements. 767 had one where the outboard slats were fluttering off the airplane on approach and a hasty late mod was required. In both cases, there was a katy-bar-the-door engineering and manufacturing effort effort to do something that allowed the program to move forward. BTW that is why the -400 has 747SP style double rudders (at least the upper rudder). All that to say, this MCAS may have been another late crisis - folks at Boeing know this yes or no, and I am not sure the news even knows to ask! It doesn't matter though - alot of passengers are no longer with us. I can assure you, the MCAS system was certified, late edition or no. I wonder how..... I believe the 737 Max will go down as another step forward in airplane safety, just like the 777 and 787 and other excellent new aircraft these past years. I hope it gets through this excruciating time of partisanship, distrust, and the 24 hour news cycle. My pension depends on it!
  8. Hi - I worked for Boeing for 43 years, as a Structures design engineer, almost all of it in Everett where the wide bodies are designed and built. I worked as an engineer on the board, a lead engineer, an engineering supervisor, and an engineering senior manager for a short time. The programs I have the most experience with were 747, 767, 777, and 787. I must choose my words carefully here. What I have seen through all of those years is an unwavering commitment to safety, and a hands-off approach to the FAA - i.e. I never saw a "cozy" relationship. Conversely, there was often an adversarial relationship - a healthy tension that resulted in safe, certified aircraft and manufacturing practices that yield great performance, quality, and affordability for our customers. Whereas one can point to some incidents, or accidents, where opinions can arise WRT actions taken or not taken, by and large Boeing has been clean - one of the cleanest big corporations on the planet. The company is a fantastic resource for our country, and a representation of what our system of government and our economy can do. Like all aircraft manufacturing companies, there are designated engineering representatives employed by the company, but also representing the FAA, that are involved in the certification process when an aircraft is on the drawing board, and also when it is in production. This is done because the FAA does not have sufficient resources (manpower) to completely oversee the process of certifying something as complex as a commercial aircraft. This is not new at all. I believe some version of the process, or relationship, has been in existence ever since commercial aviation began, or since the FAA was created. These individuals must demonstrate to the FAA their expertise in the FAR's, and expertise in their engineering knowledge, must pass tests, and must gain FAA approval for their positions. I have know many of these individuals during my time at Boeing - and with no exception I have seen nothing but a pure, uncorrupted approach to their jobs. Furthermore, it has been management policy forever that these folks must be allowed to do their job with no pressure from top management. I can see how a CNN or another news source could pounce on this arrangement as an example of big business being cozy with government - we see alot of that. But in this case, it's just not there. I think it may be because an aircraft manufacturer knows that fatal crashes are the kiss of death to their business if they are found at fault. So product safety is first and foremost. Not all companies that produce other products are that way. I can however see how such a process could be degraded with insufficient resources either on the part of the FAA, or the manufacturer. So when/if we see attacks of the cert process by the press, I hope some truthful reporting results. As for the Max - some great posts here by very knowledgeable folks. I wish I knew if the MCAS system were actually new to the Max, or just an enhancement from the previous 737 variants. It distresses me to find that one input from one AOA sensor can create an emergency situation in the cockpit, where instantaneous correction from the flight crew is necessary in order to keep the aircraft under control. Any flight critical system on an aircraft must be able to demonstrate a 1 x 10^-9 probability of failing. That is true of flight critical structure as well as systems, and has been that way for eons. Systems capable of those levels of safety are the reason commercial flight is as safe as it is. This one doesn't appear to rise to that level at all, and it seems to me should have been predicted to be so. So how did it slip by? Wish I could answer that. I have seen discussion after discussion about certifiability of an aircraft system by the experts that go into excruciating detail. How was this missed? More later.
  9. As I look through wartime photos of P-47's, I see that aircraft were not always equipped with bomb pylons, or "wing tank adapters" which is what Republic called them. But the one I am making did: No question. So the bomb pylon (Dottie Mae): The model didn't come with them, at least mine didn't. Not that they would be usable. So it has to be a scratch build. I have begun the layout activities: The lower right drawing is my side view layout 3x size. You may notice the wing lower contour is far different from what you see on the actual engineering drawings. The contour is practically flat! Well it is what it is, but it forces me to make alterations to account for it. For instance, my pylon will not have as deep a nose, and that may not look quite right. Nothing I can do about that. These pylons have many many parts, and have fairly complex shapes which are not very well defined on the drawings. For contours the reader is just directed back to "the loft" which we are not privy to. But much can be inferred from the various views on the drawings. I'll get there. There are three trouble areas that I anticipate (circled in red on the top install drawing 93C78130): First is the nose. I am going to try to wrap thin plastic around a couple of former ribs. And if that doesn't work, I will hog out the shape from a block of plastic. Maybe too much to call that a "trouble area", but it will be tedious and challenging to say the least. Second is the area right behind the aft sway brace. This is a contour transition area that is poorly defined, and even if well defined will be very challenging to create from scratch. At the moment I don't even have a plan. Third is the aft end which is occupied by a very complex casting. The part is meant to be a hinge for a stabilizing post used for one of the larger fuel tanks that were sometimes used. When not used it hinges forward to a stowed position as shown on the drawing. That casting is going to be a tiger to represent. I have no good plan yet. MOF - that part was so challenging, even the Dottie Mae has only a simple sheet metal replacement for it. See the photo above. So I have my work cut out for me - a project within a project. Bring it on!
  10. Peter - stunning work as usual. I have it on high authority (the P-51 SIG) that wartime Mustangs had a finish application on their wings which smoothed the surface, such that flush rivet heads were basically invisible, and perhaps skin butt joints as well. The advanced wing airfoil shape, which was so crucial to bringing the Mustang's baddassery all the way to Berlin and back, also was more prone to flow separation and stall - something that could be forestalled with an ultra smooth surface, so the story goes. Soooo - when skinning those wings I would not create rivet patterns my friend! BTW - I recall searching the drawing database for this surface finish callout, to no avail. I invite you to research it further to make sure. Do you belong to the P-51 SIG? What a resource! Jay Wheaton
  11. OK - pretty big update: Both LG doors are done and installed, the wings have been glued to the fuselage, the wheels are permanently fixed to the axles and held on with the axle caps. And, the centerline bomb shackle and sway braces are installed. Take a look at some pictures: First, here are some real live sway braces from Dottie Mae, along with the defining engineering drawing: And my version: They were not the easiest of projects what with the complex (and really small) shape. Here is the bomb shackle: Now the belly of the aircraft looks like this: Addition of all these underwing parts have added much needed completeness to the look of the model: Note the axle caps - I made them a couple years ago! Finally they are installed!! OK enough enough (got carried away). Not done yet! This aircraft will soon receive the wing mounted bomb pylons which are going to be rather involved. Like usual I will take you through it blow by blow. And let's not forget about the pitot mast - last because it is fragile and gets in the way. Next post you will see that, and the wing decals. Then I will need to transfer over to ready for inspection. How does one do that?
  12. OMG - what an effort on the exhaust stacks and cutout. Bravo sir, Bravo. And the spinner is just awesome. A reminder on the spinner (I learned this when I did the spinner for Miss Velma). The front end of the spinner is flat. See drawing 102-44003 (front shell): A rubber cover was pushed into the 7/8 dia hole (see drawing 104-44002) Is that cool or what? I added the flat, and added a little round filed .01 thick piece for the plug, and it turned out very convincing.
  13. One gear door down, one to go: A very dirty door - pretty lazy weathering. Maybe I will do a little more later. The placement of the door opening cylinder in the landing gear bay months ago was really a question mark. But I had no need to worry - it's just about right. The thin silver lip that is just above the door I added to the gear bay cutout on the fuselage. It's really supposed to look that way. That lip, or shelf, is why the hinge fittings need to be goose necks.
  14. Just to let you know I am alive, work has begun on the inboard landing gear doors. Here is what I want them to look like (Dottie Mae): I mean to include the following features: 1. The hydraulic actuator rod attach (rod not shown here). 2. The stainless steel doubler that has a clearance dish for the tire. 3. Two rollers that help lock the door in place with gear up (one shown above on bottom of door). 4. The two goose neck hinge fittings along with matching fittings on the wing rib. Here is my progress so far: The outer skin is .020 plastic sheet, the build-up is .156 tall by .08 thick strip, and the inner skin is .015 plastic sheet. The hardest part is to file and grind the spherical shaped dish on the inner surface, and then get the inner skin to lay down inside the dished area. Next post these will be finished, and mounted onto the wing. At that point, it will be time to permanently install the wings to the fuselage and permanently install the wheels onto the gear struts. I am approaching the finish line albeit very slowly! To go are bomb pylons, centerline bomb shackles, and pitot mast.
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