These 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...
Jump to postSimple, almost incorrect example which gives you the flavor though: Imagine an airfoil in the flow, which vibrates so that AoA is changing. Without airflow, you have a deflection, a corresponding restoring elastic force, and airfoil oscillates around some central position. Frequency, amplitude, all ...
Jump to postExcessively immature. I am very familiar with the difference between vibration and flutter, I have provided the definition of flutter. Many many moons ago I used to do ground vibration testing using Brüel & Kjær shakers and accelerometers connected to a HP FFT system doing modal analysis on a H...
Jump to postWhat is the difference between flutter and vibration in the wind from your perspective? Flutter is a specific engineering, it means an unstable, self-excited structural oscillation at a definite frequency where energy is extracted from the airstream by the motion of the structure. It can occur in b...
Jump to postGalaxyFlyer wrote:Flutter is a harmonic, aerodynamic vibration isn’t.
It’s false. Flutter is the interaction between the airflow over an aero structure and how it excites the inherent structural modes are excited. The aero structure does not know the difference between air coming from an engine or from free stream flow. The 77F/77L can have either a General Electric ...
Jump to postFun fact: The 777-200 LR GE90-115 was down rated to 110,000 lbs of thrust and designated the GE90-110. Exact same engine, just an artificially imposed limitation This limitation was imposed because testing revealed that 115,000 lbs of thrust moved so much air that flutter was induced on the elevato...
Jump to postSteelChair wrote:As I recall, they are very thin. Surprisingly thin. They probably have a very small R value.
Hence why cruise power is pretty near maximum. Near maximum by what metric? Certainly not by shaft power or fuel flow. Near maximum achievable at that altitude? From what I get from pilots here, if there is enough power to climb - it makes economic sense to do so.. Would N1 and/or EGT be near maxim...
Jump to postAnd what about temperatures? Those should be significant for engine wear. Of course, if temperature is communicated to pilots to begin with... Not sure what you're trying to get at here but EGT isn't hidden from the crew, at least not in any types I've flown. Going by the Trent 800 publication reco...
Jump to postWhat you say is second approach becomes dominant. As a passenger who prefers getting to the destination in one piece (and hence from the regulator standpoint) that's fine as long as it works. So shutdown statistics in that monitoring scenario may not tell airline cost story, but it definitely tells...
Jump to postThat is a good way of putting it. Engines lose thrust with altitude due to lower mass flow in thinner air. Hence why cruise power is pretty near maximum. Near maximum by what metric? Certainly not by shaft power or fuel flow. Near maximum achievable at that altitude? From what I get from pilots her...
Jump to postIt got me to thinking, what are the real world statistics of in flight engine shutdowns (IFSD) on ETOPS maintained airplanes? It looks like SYD-AKL requires 90 minute ETOPS. The stats these days are rather meaningless, with all the engine monitoring that is done engines are pulled before they fail....
Jump to postOn all Boeing non-737 models climb derates are a fixed percentage of full climb there. There are two climb derate settings - CLB 1 and CLB 2. The precent derates are customer selectable, but they are usually 10% and 20%. The 737 is a bit different and I’m not as familiar with it. Thanks for confirm...
Jump to postThere's a thread somewhere about derates on here. Most of them wash out in the 8-10k foot range and then resume the normal climb schedule. I'm pretty sure that only applies to the dense air conditions where it gets the most strain. Higher up you want to allow higher settings because the engine is m...
Jump to postkalvado wrote:Advantage of pressure is that it is easy to agree upon, and updates are not expected...
GPS altitude is altitude above a reference plane of a gravitational earth model, not any physical terrain. So it doesn’t correspond with MSL. https://www.esri.com/news/arcuser/0703/geoid1of3.html So while using GPS altitude wouldn’t cause any issues in cruise flight, using GPS altitude near the sur...
Jump to postMy non-pilot understanding - and hopefully someone would correct me if I am wrong - a first step to handle an engine problem is to reduce power to idle. It still triggers diversion requirement (although not as strict as full shutdown) under the assumption that a problematic engine could still run fo...
Jump to postSo you're saying it's physically impossible to fly with hydrogen on an aircraft because the storage tanks would not have the capacity nor be light enough? P.S. I see no issue with the tank not being connected to the engine. Wing tanks are also tested before they are connected to an engine. Would yo...
Jump to postSo? Is a stainless steel dewar 2x the MTOW of the ATR? https://www.airbus.com/en/newsroom/stories/2022-11-the-cold-heart-that-powers-our-zeroe-aircraft So we have a probably serious company, why is long involved in composite tanks, actually delivered some to EASA, saying "demonstrator tank (no...
Jump to postWhere do you get the 2x or more MTOW from? As if that were the case Universal Hydrogen wouldn't be doing something like this as it'd be dead before you even start. https://hydrogen.aero/product/ Do you see any actual numbers on that site? Part numbers. volumes, dry and net weights? Any actual infor...
Jump to postRJMAZ was saying "Liquid hydrogen has a quarter of the energy per unit of volume compared to jet fuel." But that is a wrong premise as energy content is by mass and not volume. Hydrogen might be low density but if you compress it to a higher density then you will get more mass per volume....
Jump to postI would beg to differ. Payload of cargo isn't the same as fuel. It is uplifted by volume but all indications on the aircraft are in mass. Your volume will vary with density but the mass stays the same. Therefore it's that what you want to know. Fuel Quantity Indications are in kg or lbs and so is f...
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