Tag Archives: door

T-45 Nose Gear Door Sequencing

With a title like that, who could resist reading this one!  The T-45 is a plane I have a close affinity with.  It was my involvement with the project that first brought me to work in the US and it is responsible for me meeting Nancy.  Aside from that, I got quite involved in many aspects of the plane’s design so feel like I know it quite well.  It did not have a smooth entry to service and went through a multitude of upgrades prior to being accepted in to service.  One of the lesser known items was the nose gear doors.

These were lumped in to a bunch of issues relating to directional stability.  The front fuselage of the T-45 is considerably deeper than the original Hawk but the design originally had the same fin and actually lost the ventral fins that were either side of the airbrake on the original.  Directional control was enhanced by adding a fin cap, modifying the rudder design and adding a new ventral fin on the arrestor hook fairing.  One other change was made too.

The carrier launch requirements meant the simple nose gear was replaced with a far chunkier assembly with dual wheels and the catapult launch bar, all of which was beefier enough to take the catapult launch loads.  Covering this all up were big nose gear doors.  These were originally either open or closed.  If you look at the doors, you can see they are like adding large fins to the front fuselage.  This is very destabilizing.  The rear doors must stay open when the gear is down but the front doors were rescheduled to close again once the gear was down, making a substantial difference in directional stability.  They have to open while the gear is transitioning and stability is reduced during this phase but it doesn’t last long.  However, if you watch the retraction and extension sequence, you get a brief glimpse at how big these doors really are.  From what I understand, a similar issue affected the F-35 and only the first airframe, AA-1, had the old single huge gear door.

The Less Subtle Bits of Dreamliner Design

AU0E2346.jpgAirliner design is a complex task with many compromises. It is not a surprise that some aspects of the design that results aren’t exactly what you would like. Today I am picking on one particular type – the Boeing 787 Dreamliner. This is almost as new as it gets in the airliner design world so you would expect it to be better than what came before.   However, having seen a number of them recently, I have been focused on two areas of the design that are rather disappointing. One is the wing root fairing area and the other is the cargo doors.

AU0E3642.jpgA nice smooth design is what the old aero guy in me likes to see and the inlets and fairings around the transition from the fuselage into the wing root are pretty ugly. They are obviously there as a result of functionality requirements but it does not look good and I imagine it comes with a drag penalty that has had to be accepted.

AU0E2336.jpgThe other area is the cargo doors. I am not sure whether this is a function of the load transfer requirements from composite to metal in the hinges but this area looks rather chunky and draggy. I know from previous projects that the nature of composites versus metals means that you can end up with some large joining fixtures to redistribute the loads but there may be other reasons I haven’t thought about. Given how smooth some metallic fuselage cargo doors are, these jumped out at me. Perhaps I have never looked closely enough at other types. Whatever the fairness of it, I just don’t like what they have done here.

Stormy Skies

While a wide swath of the Midwest was being hit by some terrible storms, the area north of Green Bay got a taster of what was going on elsewhere.  Thankfully we were spared the worst of it but there were some pretty serious thunderstorms that crashed through the area.  Elsewhere in Wisconsin some more damage was done but we were in an area that got a lot less of an effect.

As the storms approached, I saw some quite amazing cloud formations pass over our location.  The skies were really churning – not something that can be easily demonstrated with stills – but the shapes that were forming were still interesting enough to warrant some attention.

I spent a little time outside trying to record these amazing clouds with mixed results.  I also wasn’t too enthusiastic about staying outside when the storms really got going.  I didn’t have a good location to set up to try and shoot them either and besides, we had a reservation for dinner!  However, I did get a few shots and hopefully they will convey a small amount of what I saw.  If not, at least they remind me of what was happening!

Scotties on parade

A weekend break has recently taken us up to Door County in Wisconsin. We stayed in a small town called Baileys Harbor. By coincidence, the weekend that we were there, the town was holding a parade of Scottish Terriers. His parade started off with a pipe band walking through the streets followed by about 200 Scotties been walked by their owners.

This might sound like a recipe for disaster. Scotties are hardly known for their calm temperament (I will resist making any comment on their fellow countrymen) so putting 200 of them together and adding some pipes might seem like it was going to end up being a noisy affair. However, it all went off very smoothly. The dogs all trotted along without any complaint – including no complaints about the outfits at some of the owners had decided they should wear just in case we hadn’t noticed they were Scotties. I really don’t think a dog deserves to wear a fake kilt with fake bagpipes for extra effect.

A lot of people turned out to see the parade. A couple of people asked us if we had come specially for it. It was certainly fun to watch but I don’t think I would make a five hour drive each way just to see it! Interestingly, a lot of people brought their dogs to watch the parade. I’m not sure whether they think that their dogs would be interested in something because it was dog centric or not but I don’t think the other dogs were really that bothered.