There is a steady stream of Boeing 747 fleet retirements right now. This month another one occurred when the last Air France 747 flight took place. I have not seen a huge number of their Jumbos over the years but they have cropped up from time to time. It turns out that the best shots I have got have all been at SFO although these were mainly taken long before I moved here.
Anyway, farewell Air France 747s. I wonder which operator will be next?
It might be a long time ago that I did anything closely related to the engineering of fighters but there is still a part of me that is a stability and control type of guy. Watching the control inputs and responses of planes is cool as far as I am concerned. With the advent of fly by wire designs, there was considerable scope to play around with the use of the control surfaces to achieve different aims. With no direct linkages to the stick, the pilot can be totally unaware of the choices the system is making for control combinations.
The engineers may have chosen to program the trailing edges to have different deflections inboard and outboard to offload the outer portion of the wing for example. The F-22 makes use of a variety of interesting control inputs. For example, it doesn’t have a traditional speed brake. I assume this was removed for stealth reasons. Instead, the control surfaces move counter to each other. You may have inboard flaps going down and outboard flaps going up. The moments cancel out but all increase drag incrementally so the effect is like having a speed brake deployed.
Since the aircraft is also unstable, you may have tail deflections that seem at odds with the maneuver being flown. During the Chino show, the usual routine was flown (usual for an F-22 but not many other jets) and, as I look through a bunch of the shots, I see some quite unusual control inputs. If you are in to such things, these may appeal to you. Gary, are you reading this?
The winter brings days with clear skies and nice light angles. That is not all it brings, though. It can mean strong winds. One of my visits to SFO last year coincided with some very strong winds. The wind was gusting over 40kts on a regular basis. This was far to strong to allow operations on all of the runways. With the wind almost directly down the 28s, those runways were in use for arrivals and departures.
The wind might have been strong but the conditions weren’t bad for photography. The sun was actually out and the light on the planes was pretty nice. However, using a long lens was a bit more tricky with the wind since it tended to blow the lens around a lot. I spent a lot of time trying to stay in the lee of a tree to shield myself from the worst of the gusts.
Consolidation of all operations on the two runways meant that things could get pretty congested near the thresholds. Plenty of jets were lined up ready for departure in between the arrivals. Having so many jets up there is relatively unusual. It is a bit problematic for some shots though. The arriving jets are behind those awaiting departure slots. The waiting jets produce a lot of distortion from the heat of their engine exhausts. This can be quite frustrating since the number of jets means that clear space for a shot is limited.
There are more benefits of course. Having very strong winds straight down the runway means the departing jets have a big advantage. Nearly 40kts on your ASI while standing still means a lot less ground roll is needed to get airborne. The narrow bodies were jumping into the air long before they got off peninsula extending the runways out into the bay. The same was true for the wide bodies. The heavy 747s always have a longer roll but they were getting up before the cross runways. The big twins were getting up very quickly. I had a pretty good view of the 777s as they departed and got what is probably my clearest view yet of the truck rotation on the 777-300ERs – a quest familiar to the regular readers.
Fighting the wind made for a tiring day. I decided I would wait around until the Virgin 787-9 showed up and then call it quits. This was due to be one of the last big arrivals prior to the sun disappearing. When it came in, the light was very nice. I got some good shots and then packed up to go. Going back through the shots since, it was quite clear that the wind was a big factor in my shooting. The sharpness of some shots suffered but the bigger issue was tracking accurately. Far to many extremities of planes got chopped off. Despite, that, the opportunities a day like that offers made it well worth doing and I would be back in a heartbeat if the conditions come together.
The construction technique for aluminum aircraft fuselages is known as semi-monocoque. A monocoque structure takes the entire load through the shell of the structure. In airframes, the skin is very thin and so frames and longerons are joined to the inside to provide additional rigidity while the skin still takes a lot of the load. If you haven’t ever seen the cross section of an aircraft structure, you may be surprised to see just how thin the skin panels actually are. They are perfectly up to the task of pressurization and bending loads so no need to panic.
An outcome of this design approach is that the panels between the frames and longerons can experience some load directions that induce a measure of buckling. Nothing that is beyond their elastic limits but something that can be apparent if the light comes from the right angle. The lower side of the rear fuselage of the Boeing 757 is an area that is susceptible to this in certain flight conditions. I saw a number of them recently – both -200 and -300 models – and they both were showing visible distortion of the panels. The sun angle meant that the shadowing of these areas was apparent.
The 757 is by no means the only aircraft to experience this phenomenon. The B-52 Superfortresss is a jet that shows this effect on plenty of occasions. I have heard people comment on it being a function of the age of the airframes but it is more of a result of the design of the basic structure than anything else. Certainly nothing to be immediately concerned about.
Not long ago I complained about the dirty condition of a China Eastern A330. At the time, I thought it might be a non-standard jet because the livery was basically white with a couple of distinguishing marks. It turns out that I hadn’t appreciated that China Eastern have replaced their previous colors with a new and less colorful scheme. Since then I have seen some 777s come in with the new scheme. In an era of relatively bland airline colors, it seems to me that China Eastern have gone a stage further and taken any interest at all from the livery. Not a cool effort on their part I think. They should check out what China Southern is doing by comparison.
The repetitive nature of the same airlines and the same types is what you expect of airports these days. Every once in a while, though, the airlines put some extra decoration on their aircraft. Usually you can see that there is something there before you get to see what it actually says. JetBlue have an Airbus A321 that is apparently their 200th aircraft. It has a big decal on the rear fuselage to highlight this fact. It apparently joined them over a year ago so a bit late for congratulations.
While the world’s 747 fleet is progressively running down, United is still a big operator of the type and SFO is a focus of their operations of the type. Consequently, during the surge of departures to Asia in late morning, you will have a pretty steady stream of Jumbos taxiing out and taking off. While Roger and I were out, a couple of them taxied out at the same time. We had one holding short of 28L and the other was in the gap between 28L and 28R as incoming aircraft approached. I joked with Roger that the two of them should line up on parallel runways and depart in formation.
When the inbound jets had landed, both aircraft moved forward again and, sure enough, they lined up on both runways. We couldn’t help but laugh at this since they seemed to be following our instructions. You will regularly see parallel departures on the 01 runways but we couldn’t believe that we would have the same thing here. Sadly, we were right. The closer jet departed first and was then followed a short while later by the second. It would have been very cool to see them climb out side by side but that was a bit too much to ask.
Airliner 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.
A 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.
The 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.
Unfortunately, I have a rather large backlog of images that I haven’t done much with. This is sometimes the result of having a number of events in a short space of time and other times it is the result of laziness! Last year I covered the Planes of Fame show at Chino for GAR. I got a lot of shots while I was there and I needed a selection to illustrate the piece so I dived in, found some good examples, worked on those and put them into the feature.
Unfortunately, I never got around to undertaking a proper run through of the shoot. I only realized this recently so I have started to go through the images when the time allows. One part of the show I really liked was the twilight show on the Friday. This included a display by the USAF F-22. In the last light of the day, the airframe looked really great.
Running through the shots I found a few of the jet that I really liked. (I found more than will work for this post and some that I like for various reasons but won’t really gel with most people.) As a result, here are a sample of the shots I have been finding. Now I am starting to think about air shows this year for the first time. I might have to go to this one again!
SFO controllers are known to make some late runway changes for the arriving aircraft. The two runways are very close together to the sidestep maneuver required is not too drastic but it is still not necessarily something the crews want to deal with. A Southwest 737 was on approach and passing near us on the shore when it apparently got the change instructions. We got a sudden topside view as it turned towards us followed by a reversal of bank as it straightened up on the new runway. Compared to the average arrival, this was quite a bit of excitement! Also, if you look closely, you can see another Southwest jet in the background that had just departed.