Sometimes it's all about money... That is also the most fundamental of basics, though. Money is an invention of and concern for humans. The universe would be indifferent to such matters. Regards, JetMech Sort of. Money is a simple optimisation metric, and in that sense similar may exist outside of ...
Jump to postYes, it is all still about submicroscopic particles. It all WAS, in fact, F=ma. Just can get really complex. It certainly seems that it's all about the smallest of entities and most fundamental of basics Regards, JetMech Sometimes it's all about money... That is also the most fundamental of basics,...
Jump to postA bit of detail: "UltraFan has been designed to be 25 percent more efficient than the first generation of Trent 700 engines or ten percent better than the Trent XWB, have forty percent lower NOx emissions, and produce 35 percent less noise. And it is ready to accept 100 percent SAF. At a later...
Jump to postFlight hour pay cost is really minimal in the grand scheme of things because these are often short flights. So let's say a pilot earns $95 an hour at Acme Regional Airlines, but that same pilot flying for BigMainliner is paid $150 an hour. The flight is blocked in at 1.5 hours so the difference in ...
Jump to postVery deep, but totally non-actionable as well. He was very fond of saying, "it's just F=ma" no matter how complex the equations on the blackboard were. The nature of the universe appears to be a handful of very fundamental forces and particles that combine in an infinite number of ways to...
Jump to postThis reminds me of a quote I read in the book, Fundamentals of Aerodynamics, by John D. Anderson Jr.; "the aerodynamic forces and moments on the body are due to only two basic sources: 1. Pressure distribution over the body surface 2. Shear stress distribution over the body surface No matter h...
Jump to postAirbus' airport planning guide shows approximately 1650m = 5500' minimum(<165t), 2100=7000' maximum(235t) required dry runway landing distance at sea level for A350-1000.
Jump to postAirbus' airport planning guide shows approximately 1650m = 5500' minimum(<165t), 2100=7000' maximum(235t) required dry runway landing distance at sea level for A350-1000.
Jump to post"What you basically need to know is that the faster you go, the harder and harder it gets to go even a lit bit faster." This reminds me of a quote I read in the book, Fundamentals of Aerodynamics , by John D. Anderson Jr.; "the aerodynamic forces and moments on the body are due to on...
Jump to postYou reenable Wi-Fi, while keeping cellular services off. Flight Mode only disables your cellular 4G/5G service. WiFi is not inhibited in in flight mode. For me, flight mode disables all radio interfaces, including wifi and bluetooth. Don't want to re-ignite that discussion, but that may be a good i...
Jump to postFlight Mode only disables your cellular 4G/5G service. WiFi is not inhibited in in flight mode. For me, flight mode disables all radio interfaces, including wifi and bluetooth. Don't want to re-ignite that discussion, but that may be a good idea for critical stages of flight - recent radio altimete...
Jump to postAt slower airspeeds, the control have a reduction in authority—a function of less airflow over the surfaces. Plus, near the ground, there’s potentially more turbulence requiring inputs to remain laterally level, tracking the runway and affecting the vertical path. It’s not forces, it’s pressures. M...
Jump to postI don't think 737-200s have a lift dump like a Hawker, but they appear to be doing something similar. You can see the flaps are only at 15 on approach, which makes total sense at a place like Cusco. Once on the ground, throw everything out to stop the airplane, given the very high ground speed. A d...
Jump to postA dumb question: while flaps would definitely increase drag, wouldn't they also unload wheels and reduce wheel brakes efficiency? Not a dumb question at all. The speedbrakes (i.e. spoilers) destroy the lift produced by the wings and would make any unloading due to flap extension negligible. If the ...
Jump to postI don't think 737-200s have a lift dump like a Hawker, but they appear to be doing something similar. You can see the flaps are only at 15 on approach, which makes total sense at a place like Cusco. Once on the ground, throw everything out to stop the airplane, given the very high ground speed. A d...
Jump to postWas there ever a rear-end accident for the planes?
I can certainly remember wingtip events of various severity, there are some pushback accidents - but I don't remember anything about occupied cockpit damage in ground collision.
This is due to wind speed, as anyone operates over high terrain knows. While Mt. Everest has the accepted tallest peak above ground, it is not the tallest mountain from base to peak. Mt. Everest sits on the Tibetan plateau, as wind passes over the plateau it accelerates and causes a drop in pressur...
Jump to postTrue, basically from what I’ve read, the bodies are shutting down above about 24-26,000 feet. Most of deaths are on the way down when the body simple collapses. Ed Viesters has some great climbing books. “The summit is optional, getting down us mandatory”. For that specific climb, weather change ma...
Jump to postTrue, basically from what I’ve read, the bodies are shutting down above about 24-26,000 feet. Most of deaths are on the way down when the body simple collapses. Ed Viesters has some great climbing books. “The summit is optional, getting down us mandatory”. For that specific climb, weather change ma...
Jump to postEverest has been climbed without O2; but they’re “freaks of nature” n the ability to process limited O2. Looks like Everest is at the very edge of human capability, no-oxygen climbs occurred when atmospheric pressure was on the higher side. While armstrong limit is about twice as high, it is just t...
Jump to postIt might be that on the ground, there is a small measurable difference in weight on the wheels, between the two sides. However in flight, the center of lift on each wing is so far out from the centerline, that those forces and moments would dominate the aircraft by a large margin. So basically the ...
Jump to postLook at it in such a way: 2 outer seats cancel out, so entire imbalance is a aisle seat on 3 side shifted off center by half the width of an aisle. And that aisle isn't wide...
Jump to postThese are all good points - but none of them solve the problem. How do you organize an influx of aircraft (almost exclusively corporate/GA) on specific (predictable) days? This isn't a one-off event like the Derby or SuperBowl - its like having those days, twice a week - for three months straight. ...
Jump to postVery remotely related topic...
Many cities are giving some advantage to public transportation running on public streets. Multiple reasons for that, from reducing overall number of vehicles on the road to assumed environmental benefits....
Looking at it another way, those speeds as more conservative, since you aren't as near flap overspeed. Maybe they had pilots overspeeding the flaps a bit too often. What about the other limit? Lower speed and higher bank angle would translate into higher aoa, and smaller stall margin. Or there's en...
Jump to postAre there limitations on rotation angle for longer 787s?
Jump to postWell at least Southwest is still requiring ATP to apply. My airline dropped the requirement for an ATP certificate required. Now the requirement is to have the ATP written test results, but not require an ATP certificate. It will do what the regionals have had to do for years and offer the ATP-CTP ...
Jump to postThe maximum speed for sharp turns while taxiing depends on the type of aircraft. Generally, the maximum speed for a 737-800 is around 30 knots (35 mph). However, this can vary depending on the conditions of the runway, the weight of the aircraft, and the type of turn being made. For instance, a tig...
Jump to postIf that is for high speed turn-offs... Is that airline operating at the hub where they usually exit to one side due to runway config? High speed runway exits are a bit of a different animal, as far as I understand; hopefully pilots would elaborate...
Jump to postAs it stands we're seeing damage at the shoulders on one side and we're thinking inertia forces during a sharp turn might be causing the damage. So for example, sharp turn right, and it's the left side getting damaged through frictional abrasion as the plane is still technically pushing the tire &q...
Jump to postThese are all theories based on what people choose to believe about Boeing. Again there is zero supporting evidence. I've asked multiple times for people to post their evidence. Opinions are not evidence. Nor is lack of disclosure evidence. Nor is lack of disclosure in any way unusual for pricing i...
Jump to postIf it was a cheap repair, Boeing would certainly comment about it. So lack of information is an indirect evidence of high cost. There could easily be reasons for Boeing to proceed regardless of high cost. 1. reputation/PR 2. learning actual costs on an actual case as opposed to preliminary estimate...
Jump to postI wrote : "the real costs were never revealed " So i can also say : If you have evidence the repair was economical, you are welcome to post it here When an aircraft is written-off because it can't be economically repaired, that will be evidence. Haven't seen that yet, apart from the two 7...
Jump to postJust asking, but am I correct in assuming this kind of repair is more labor intensive for composites than metal frame? It takes longer due to the multiple layers involved and curing times. But is essentially the same process, remove the damaged section, prepare the surfaces for the patch, then appl...
Jump to postlooks perfectly metallic: A serious situation occurred in March 2010 to an Embraer EMB-145LR. The aircraft sustained a lightning strike while on approach. The flight crew subsequently encountered elevator control binding, although they were able to land without further incident. A post-accident ins...
Jump to postlooks perfectly metallic: A serious situation occurred in March 2010 to an Embraer EMB-145LR. The aircraft sustained a lightning strike while on approach. The flight crew subsequently encountered elevator control binding, although they were able to land without further incident. A post-accident insp...
Jump to postIf you think those errors are bad, you should see the ones humans made. Indeed, the point is that everything in aviation has redundancy. This was dealt with fast but should never have happened. Mistakes do happen no matter what. Question is how to manage them properly. In this particular case, mayb...
Jump to postWhat do you mean by "crosswind"? Looking at Seattle, they have north-south runways and those are pretty much aligned with prevailing winds
https://climate.washington.edu/windrose ... ndRose.jpg
Question: if I drive my car at 60 kmh it will comsume more fuel than going at 90 kmh or so, but if I go up to 130, it gets thirsty again (I do know gears play a role in it and can and usually drive on 4th/5th with my stick VW). Do airplanes work that way too? Of course its the same. A bit more comp...
Jump to postAll that and Gen X and Gen Z are accustomed to flying, don’t think anything of it, being union and wearing a uniform isn’t “fashionable” among the tattoo, pot smoking crowd. Stereotyping, sure, but the stereotypes exist for a reason. Few of today’s generation are ready to give blood to be a pilot. ...
Jump to postI don’t disagree, but it has been very successful in Europe. For the investment the company puts up, there has to be a reciprocal commitment. The USG practices just that with service commitments. But that does go to the cultural issues. The US has never embraced the career apprenticeship idea. Educ...
Jump to postEh, that depends how the airline is calculating it. If their hours are in the Osprey, which a lot of pilots now are getting much of their time in, Southwest counts it as a zero turbine time. This became a lot more robust after Jon Kotwicki embarrassed the industry a bit. Come on now, you have to se...
Jump to postWho pushed the legislation? Chuck Schumer, NY politician, who continues to defend. Second, 250 hours which might not ever involve being inside a cloud isn’t the experience levels that passengers expect. Transporting airline passengers should be done by Airline Transport Pilots, not students with fe...
Jump to postIf I had a penny every time I see a poorly written textbook... If the design regulations had a definition of flutter I would have quoted that, it doesn’t . A textbook definition is what anyone in industry would revert to when interpreting the regulations. For one, it doesn't allow you to distinguis...
Jump to postThere are certainly propulsion-induced flutter effects as airflow interaction doesn't care about the source of airflow. three top links from Sure there are flutter modes associated with propulsion, however the claim made above was the GE90-115 had to be derated to the GE90-110 as flutter was induce...
Jump to postIt helps to realize that the experience requirement is a stand-in for judgement and emergency skills, which are difficult to measure directly. The premise is that these attributes are more highly developed in experienced pilots. Which is statistically true. But as with all statistical results, you ...
Jump to postDear AviationGeek, There are likely several factors involved. The most important is likely the reduced air density. This will reduce the energy carried by the sound/shock waves coming from the engine. Contributing factor is the speed increase - causing more white noise inside the cabin and re-shapi...
Jump to postWell, your definition of flutter please. Other than that it is a problem affecting both civilian and military airplanes, of course. and without referencing "good working understanding of non-applicable equations". Some references may be helpful, though. You really don't care what is the r...
Jump to postIIRC the CSM/G is also a dinky 5kw unit. Barely enough to keep the battery charged, the Captains instruments and a few of the flight control computers operating. I've never known of an incident whereby any airplane was down to that generator. If you're down to that, you're in serious trouble. This ...
Jump to postThis is drivel, the jet exhaust over the tailplane as cited above is not flutter. Lots of aircraft types experience similar. Your posts are just red herrings, and do not address the claim at all. I was very familiar with flutter, in air, in water, and in space. The engineering principles have not c...
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