Christmas Day, Azerbaijan Airlines Flight JS-8243 crashed while attempting an emergency landing at Aqtau Airport in Aktau, Kazakhstan. There were 67 passengers and crew aboard; at least 38 died in the crash, and the body count may climb as hospitalized passengers succumb to their injuries. Russian aviation authorities blamed the loss on a massive bird strike, but the intact tail section bore the tell-tale marks of a hit by a missile fired from an SA-22 Greyhound (Russian name: Pantsir) surface-to-air missile system. Read the background in my post: Azerbaijan Airline Crash Was Most Likely Caused by a Russian Missile.

Despite warnings from the Kremlin not to speculate on the cause of the crash, Azerbaijani officials have told the media Flight JS-8243 was brought down by a Russian missile. //

It was the drone attack, not fog, that prevented JS-8243 from landing.

Near Grozny, the plane was hit by a Russian missile. The plane asked to divert to airports at Makhachkala or Mineralnye Vody, but permission was denied, and it was told to land at Aqtau Airport. Essentially, it was forbidden to land in Russian territory. As the plane left the Grozny area, it was subjected to GPS jamming and other electronic warfare effects. "According to data, the plane’s GPS navigation systems were jammed throughout the flight path above the sea."

By now, the plane had lost steering, and the pilot and co-pilot were managing direction and altitude by using engine power. This is what the flight looked like with altitude changes. //

By any standard, the flight crew on JS-8243 were heroic. By keeping the fatally damaged aircraft in the air and accomplishing a controlled crash near the Aqtau Airport, they saved nearly half the people on board. //

flyovercountry
11 hours ago
It needs to be said over and over, the reason why the Russians denied landing anywhere except Kazakhstan is the hope the airplane, and evidence, would be at the bottom of the Caspian Sea.

Four backcountry airstrips in Idaho’s Frank Church River of No Return Wilderness known as the “Big Creek Four” have been deemed emergency use only as outlined by a recent legal settlement.

The ruling stems from a lawsuit between environmental groups and the U.S. Forest Service, with the State of Idaho intervening on behalf of recreational aviators. In its complaint, environmental advocates have stated that aircraft use of the Big Creek Four is damaging wilderness character, wildlife habitats and the area's legally protected solitude.

The recent ruling notes that the airstrips will remain technically open for emergencies, but recreational access will be prohibited, with both usage and maintenance subject to monitoring—a major setback for recreational flyers. //

bbgun06
A grass strip that is not used recreationally won’t be maintained for emergency use.
I’d hate for a pilot experiencing an emergency to die after attempting a landing there.

scarlson
This is exactly correct. I know many pilots who help maintain back country strips in Idaho and Montana. Pilots are the least impactful on the environment and what exactly is “damaging the wildlife character”? //

jbmcnamee
I would hope that the NPS also banned surface vehicles with ICE motivators, such as four-wheelers, motorcycles, AWD pickups, etc, or this whole thing is pretty much a sham. Ground vehicles do far more damage to the environment that an airplane does. Airplanes don’t leave trails and ruts in the forest, run over animals, possibly spark fires from poorly maintained exhaust pipes or overheated catalytic converters. Pilots rarely leave their trash behind, throw beer bottles and cans in the brush or use the trees and animals as target practice with the gun they brought along “just for fun”. In fact, if you were to ask park rangers what their biggest problems are for keeping the parks “pristine”, i doubt that pilots and airplanes even make the top ten. //

Slipstream
New backcountry rules from people who never leave the city.

Over 7-8 December, much of Flightradar24’s most tracked flights list was occupied by flights to, from, or near Syria as rebels entered Damascus and news spread that Syria’s Bashar al-Assad had been deposed. With the Russian government announcing it had granted Assad and his family asylum and they were in Moscow, we began to ponder Assad’s possible paths to Russia.

The following options present to us the most likely scenarios, though there are certainly multiple variables that leave open the possibility of additional options.

In an internal American Airlines Jetwire for employees, the company shared what happened to a group of school children visiting Washington, D.C. from Bermuda on June 15th.

Seventy one students and their chaperones had flown non-stop to Washington’s National airport on American. They were ticketed on a connecting flight back through Miami, and their DC to Miami segment was delayed by weather. They were going to miss their connection home. //

So American Airlines decided to add a dedicated flight just for this school trip. //
Since National airport is an American Airlines hub, and crew base, they were able to pick up crew that were on reserve to work the trip. They used a 128-seat Airbus A319 dedicated to the group. //

This was an even more expensive move that American made for these passengers than it seems at first glance. That’s because they didn’t just have to fly an extra plane to Bermuda – they had to get it back, too. They didn’t need to operate an extra Bermuda departure that day. So American paid to ferry the plane back to National airport, too.

The curtains are beginning to close for the A-10 Thunderbolt II (aka Warthog). The United States Air Force is set to retire 56 in fiscal year 2025 (around 20% of the remaining inventory), reducing the number of A-10s in active service to around 200. Meanwhile, the US Air Force has stated it is about to retire the last of its Warthogs based in South Korea, and these will be replaced by F-16 Fighting Falcons (upgraded with fifth-generation-like software).

Emails and tool-tracking software weren't heeded, but nothing scary happened - except to the nylon tool

Have you ever looked up at an aircraft and wanted to know exactly what type of plane it was? Having already taken a look at the key Airbus and Boeing differences, we explore the important features for identifying the wide array of aircraft in the Boeing long-haul fleet.

Gone are the glory days of the Boeing 747, the 'Queen of the Skies'. The first commercial double-decker aircraft flew in 1969, and though several are still flying today, only a few airlines operate the type on commercial passenger flights. According to data from Cirium, an aviation analytics firm, there are only four airlines operating 747s this month: Air China, Korean Air, Lufthansa, and Aeroflot. //

In October 2014, 33 airlines operated 747 passenger flights, and British Airways (BA) had the most. Ten years ago, 12,171 747 flights were scheduled worldwide, more than 2,000 of which were operated by BA. More than half of BA's 747 flights were to and from the United States (US). //

Data shows that in October 2014, 1,112 flights were scheduled to and from the US on BA 747s. This included 11 cities and more than 350,000 seats. It should come as no surprise that the busiest 747 route was from Heathrow to John F. Kennedy International Airport (JFK) in New York. Ten years ago, there were 215 flights scheduled in each direction to JFK on 747s, up to eight flights in one day.

Jet engines are known for their unique sounds, from the powerful roar of takeoff to the soothing hum of cruising altitude. For some, the distinct noise of different jet engines can evoke excitement and nostalgia. Whether it’s the distinctive buzz of an RB211 or the roar of a GE90 which sound resonates with you most? Let us know and share your thoughts!

The 51 Factory has been established with the goals of supporting the legendary P51 Mustang, British Spitfire, and other Rolls Royce or Packard Merlin powered aircraft of the WWII era.

These superb aircraft powered by 1650 cubic inch, over 1500 hp, liquid cooled V-12 engines, represented some of the most advanced technologies of the day, and most certainly greatly contributed to the allied victory, both in the Pacific, and in Europe.

The fighters developed in WWII are the pinnacle of piston engine, propeller driven aircraft performance. Even today, the fastest piston engine aircraft in the world are modified WWII fighters with Rolls Royce/Packard Merlin V-12’s, as seen at the annual Reno Air Races.

Around 0800 hrs of 22 December 1992, the Boeing 727 of Libyan Arab Airlines, registered as 5A-DIA, underway on Flight 1103 from Benghazi to Tripoli, was approaching the Libyan capital. The ground control advised the crew per radio to hold its position at 1,067m (3,500ft) above the Papa Echo beacon, about 10 kilometres (5.4nm) from Tripoli International for three minutes, due to military traffic. The ‘military traffic’ in question was a MiG-23UB of No. 1023 Squadron, crewed by Captain Abdel-Majid Tayari and a novice pilot. Following the take-off from Mitiga AB, the ground control advised Tayari to climb, turn and head towards Papa Echo.

Unaware of the airliner ahead of him, the seasoned fighter-pilot followed instructions of his ground controller to the dot and comma.

Moments later, Tayari and the student in the front cockpit were shocked to sense a detonation on the underside or below their aircraft. A fire broke out. A friction of second later, they saw the big fin of the Boeing 727 right in front of them, already separated from the airliner – and then Tayari initiated an ejection. The airliner disintegrated while still on approach to Tripoli International, killing all 157 of its crew and passengers.

The ‘negative effects of international sanctions’
Barely surviving this tragedy – Tayari suffered multiple fractures in his right hand during ejection – the crew of the MiG-23UB was shocked to find itself jailed in the hospital of Mitiga AB. The investigation of the Libyan authorities – unfairly – blamed them of either colliding with the Boeing 727, or opening fire and shooting it down: many of their superior officers and civilian servants wanted them hung on the Green Square in Tripoli.

….actually: Gaddafi ordered the flight to be shot down to demonstrate ‘negative effects of international sanctions’ – imposed on Libya after the bombing of Pan Am Flight 103 in 1989: because of numerous embargos, Libyan Arab Airlines could not fly its planes safely, and thus the victims of the crash were supposed to be presented as victims of ‘Western terrorism’. A bomb with a timer had been placed on board the Boeing 727: when this failed to detonate, Gaddafi personally ordered the aircraft to be knocked out of the sky….

Then it was time for the individual interview. The head of training and the HR guru sat me down and weren’t quite sure what to make of me. I was clearly the first (and probably only) F-14 pilot they’d ever interviewed, so they fumbled with questions like “Um… what makes you think you can handle a 250-knot turboprop?”

‘Then came the clincher: “So, why should we hire you versus all those other people out there?” They expected an answer involving hundreds of carrier landings, flying supersonic, blah, blah so I must be a great pilot. Instead, I thought for a second and said “I’m sure any of us can fly your planes just fine. I’d like to think I’m the sort of person who you can sit next to for ten hours, and not want to slug.”

‘The interview screeched to, a halt. Director of training looked at the HR dude and said “Write that down.” HR said “Already got it.” They thanked me, shook my hand, and I knew I had the job.’

Schiphol will invest €6 billion over the next five years to improve infrastructure. //

The announcement comes amid an 11 per cent year-on-year increase in passenger numbers throughout the first half of 2024, whilst capacity also increased 12 per cent year on year with 230,417 flights recorded between January and the end of June.

In 2023, the hub welcomed more than five million passengers in 2022 but announced that charges will increase by 14.8 per cent in 2024, higher than the 12 per cent rise that was previously anticipated. Schiphol CFO Robert Carsouw said in a statement: “We've notified the airlines and understand that they're not very pleased. At the same time, it's necessary for the quality at Schiphol and for our financial position. It's also how the legislation works. In good years we are not allowed to profit from airport charges and so in bad years we cannot afford any losses.” The airport - which did acknowledge that the charges paid to them by airlines are "strictly regulated by legislation" and cover costs such as runway maintenance, security and cleaning. The CFO added: "Simply put, Schiphol is not permitted to make any profit from airport charges. If what Schiphol earns in airport charges exceeds the costs incurred from facilitating the airlines, the additional revenue is 'given back' to the airlines

Thursday 2nd April 2020 15:11 GMT
BJC
Millisecond roll-over?
So, what is the probability that the timing for these events is stored as milliseconds in a 32 bit structure?

Reply Icon
Re: Millisecond roll-over?
My first thought too, but that rolls over after 49.7 days.

Still, they could have it wrong again.

Re: Millisecond roll-over?
I suspect that it is a millisecond roll over and someone at the FAA picked 51 days instead of 49.7 because they don't understand software any better than Boeing.

Thursday 2nd April 2020 17:05 GMT
the spectacularly refined chap
Reply Icon
Re: Millisecond roll-over?
Could well be something like that, the earlier 248 day issue is exactly the same duration that older Unix hands will recognise as the 'lbolt issue': a variable holding the number of clock ticks since boot overflows a signed 32 bit int after 248 days assuming clock ticks are at 100Hz as was usual back then and is still quite common.

See e.g. here. The issue has been known about and the mitigation well documented for at least 30 years. Makes you wonder about the monkeys they have coding this stuff. //

bombastic bobSilver badge
Reply Icon
Devil
Re: Millisecond roll-over?
I've run into that problem (32-bit millisecond timer rollover issues) with microcontrollers, solved by doing the math correctly

capturing the tick count

if((uint32_t)(Ticker() - last_time) >= some_interval)

and

last_time=Ticker(); // for when it crosses the threshold

[ alternately last_time += some_interval when you want it to be more accurate ]

using a rollover time

if((int32_t)(Ticker() - schedule_time) >= 0)

and

schedule_time += schedule_interval (for when it crosses the threshold)

(this is how Linux kernel does its scheduled events, internally, as I recall, except it compares to jiffies which are 1/100 of a second if I remember correctly)

(examples in C of course, the programming lingo of choice the gods!)

do the math like this, should work as long as you use uint32_t data types for the 'Ticker()' function and for the 'scheduld_time'; or 'last_time' vars.

If you are an IDIOT and don't do unsigned comparisons "similar to what I just demonstrated", you can predict uptime-related problems at about... 49.71 days [assuming milliseconds].

I think i remember a 'millis()' or similarly named function in VxWorks. It's been over a decade since I've worked with it though. VxWorks itself was pretty robust back then, used in a lot of routers and other devices that "stay on all the time". So its track record is pretty good.

So the most likely scenario is what you suggested - a millisecond timer rolling over (with a 32-bit var storing info) and causing bogus data to accumulate after 49.71 days, which doesn't (for some reason) TRULY manifest itself until about 51 days...

Anyway, good catch.

US air safety bods call it 'potentially catastrophic' if reboot directive not implemented //

The US Federal Aviation Administration has ordered Boeing 787 operators to switch their aircraft off and on every 51 days to prevent what it called "several potentially catastrophic failure scenarios" – including the crashing of onboard network switches.

The airworthiness directive, due to be enforced from later this month, orders airlines to power-cycle their B787s before the aircraft reaches the specified days of continuous power-on operation.

The power cycling is needed to prevent stale data from populating the aircraft's systems, a problem that has occurred on different 787 systems in the past. //

A previous software bug forced airlines to power down their 787s every 248 days for fear electrical generators could shut down in flight.

Airbus suffers from similar issues with its A350, with a relatively recent but since-patched bug forcing power cycles every 149 hours.

What is the max skin temperature?
I heard/read somewhere that the reason the max skin temp of the real thing was 127℃ was because it made the maths easier for the engineers. Which makes sense after a little thinking.

I also heard about an SR-71 crew who were buzzing around the Caribbean being alerted to "Civilian traffic at your altitude" and being "WTF?"

Happy
Re: What is the max skin temperature?
What, so _skintemp could be stored as a 7-bit uint?

So... if any part of Concorde's skin ever reached 128°C, it would instantly flash-freeze?

Re: What is the max skin temperature?
127+273=400. (K)

Re: What is the max skin temperature?
Maximum skin temperature of 127ºC was set by the properties of the aluminum alloy used on the Concorde. Sustained exposures to temperatures above that would weaken the alloy. Sustained Mach 3 flight requires use of Titanium or stainless steel.

IIRC, the SR-71's typical operating altitude was a few km higher than the Concorde.

Re: What is the max skin temperature?
There's an interview with the SR71 pilot in the Omegatau podcast.

He was describing how he was pootling around over Cuba doing SR71 type things, when asked to look out for civilian traffic at his flight level

His observation was that he was wearing a space suit and peeing in a tube, while these businessmen flew past in shirt sleeves eating dinner and sipping champagne.

Tom Lopes flew a 2018 Cessna 172S Skyhawk SP on a ferry flight between California to Hawai’i. He flew the small single-engine general aviation aircraft an incredible 2,425 miles over more than 17 hours over the Pacific Ocean to the aircraft’s new home. This feat is even more mind-blowing when you learn that this was a nonstop flight that was more than three times the normal range of the aircraft. Here’s how Lopes did it.

Perhaps the coolest part about this journey is the fact that it’s something that Lopes has done before. Tom Lopes, the owner of Gateway Air Center, is a ferry pilot. He’s the guy you hire when you’ve just purchased a plane from somewhere far away and you want it delivered to where your home base is. Two years ago, Lopes flew the same crazy journey we’re talking about today. Lopes flew a different Cessna 172 between Merced Regional Airport/Macready Field in Merced, California, and the Daniel K. Inouye International Airport in Honolulu, Hawai’i. I wrote about that trip two years ago and it took Lopes over 18 hours to fly the little plane 2,521 miles, or 2,190 nautical miles.

There may be no greater debate amongst pilots than the “rich of peak” or “lean of peak” (ROP vs. LOP) exhaust gas temperature method of leaning the aircraft engine. //

So that leaves us with the question; is it better to operate rich of peak or lean of peak?

Some engines achieve maximum economy range on the leaner fuel side of peak exhaust gas temperatures (EGT) and maximum power on the rich side of peak EGT. Some achieve both on the rich side of peak EGT. The ultimate answer comes from your engine manufacturer’s engine operator’s manual (EOM).

Exhaust Gas Temperature (EGT) provides pilots a way of monitoring the fuel/air mixture in the engine. It uses the stoichiometric mixture (where Fuel and Air are perfectly balanced so that there is no unburned fuel and no unburned oxygen at the end of the combustion event) as a reference: At this mixture the EGT is at its hottest ("Peak EGT"). Making the mixture richer or leaner will reduce the EGT, and all other mixture settings are described in terms of "Degrees Rich of Peak" or "Degrees Lean of Peak". //

The area of the chart from peak EGT to about 100 degrees Rich of Peak is often referred to as "The Red Box" -- in this range the fuel/air mixture has a low detonation margin, and the combustion event is producing the most internal stress on the engine components (cylinders, pistons).
As you can see from the Lycoming chart the Cylinder Head Temperature (CHT) peaks in this range, and there is a risk of exceeding the CHT limits and seriously damaging your engine by operating in this range for extended periods of time, particularly at high power settings.

The Terminal Procedures Search application allows searching, viewing, and downloading of the U.S. Terminal Procedure Publications (TPPs) as PDF files