Russian airliner crashes shortly after take off

a reply to: RadioRobert

ok....a new look at it there cool...thanks

I was a ground guy for avionics for that FB111-F model.....thrill to sit in one on midnight shift with my buddy with the flight line ok....I was A shop.....Avionics

Master switch on and play with the attack radar set from the ramp we could see the telephone poles and mountains at Mountain Home

a reply to: Woody510

Yeah. They deiced, then got delayed in line to depart, and elected to depart instead of going back to deice again.

a reply to: Zaphod58God love em.....

Died doing what they loved, huh

would the A-148 have inertial separators...idk....curious does a turbofan just crunch through ice chunks breakin off the cowling....an ice chunk hit in London on camera yesterday....just curious bout that

originally posted by: GBP/JPY
a reply to: RadioRobert

ok....a new look at it there cool...thanks

I was a ground guy for avionics for that FB111-F model.....thrill to sit in one on midnight shift with my buddy with the flight line ok....I was A shop.....Avionics

Master switch on and play with the attack radar set from the ramp we could see the telephone poles and mountains at Mountain Home

Well, look at it this way, an FB-111 at high aspect ratio (unswept) has a much better coefficient of lift. For a given speed that means more lift. That's a good place to be for takeoff and landing or a subsonic cruise where endurance/fuel burn is more important than speed.
At higher speeds, the Vark gets much lower transonic drag and gets bounced around a lot less down low (a severely underrated problem for pilots, systems, and airframe alike) with a lower aspect ratio wing (swept).
If you wonder why it doesn't need better coefficient of lift down in the weeds instead, remember that total lift is related linearly to the wings coefficient of lift, but increases by the square of velocity! So it needs less quite a bit less coefficient of lift at high speed. Handy.

a reply to: Zaphod58

The biggest issue with that was they already saw fluctuating power levels before they left the ground after the used the reversers -- they should have realized.

a reply to: RadioRobert

Yes they should have. That was straight up pilot error. I was referring to the wait between deicing and takeoff with regards to this one though.

Initial indications from the FDR are that the crew was dealing with incorrect airspeed indications, most likely caused by icing on the pitot tubes.

www.rt.com...

Experts from the Ukraine are waiting to head to Russia to assist with the investigation, and the US has offered to assist as well.

Another report just out that the crew failed to activate the pitot heat before takeoff. They switched to autopilot, but went back to manually flying after they saw differential speed indications. One airspeed indicator showed 0 for airspeed.

www.chicagotribune.com...

a reply to: Zaphod58

Do you think they stalled and couldn't recover it?

a reply to: Woody510

Possibly, but with a 0 speed indication, they may have pushed the nose over to try to accelerate, then couldn't recover.

According to the second article, they went between 30 and 35 degrees nose low. At 6800 feet, they wouldn't have much time to recover.

Geez, This is a nightmare of bad piloting.

It's tragic that 71 people died because of several factors:
1. Failure to follow checklists/procedures
2. Lack of ability to lose an instrument and maintain flight.
3. An overeaction to the loss of the airspeed gauge. 30-35 degrees, geez.

I had an incident where I lost my airspeed indication. Actually, both me and my RIO lost it (which was weird in the F-14 since they are independent on either side of the aircraft). Regardless, we were in a climb, in IMC, at full power. As soon as the gauge locked, I just kept the other indications steady. I knew (because I studied and practiced) that my climb AOA should be about 10.5 units. I also could watch my altimeter and VSI and keep it steady, to a bit lower, so I could safely climb, but not burn airspeed.

Regardless, should you lose airspeed indications, it's unlikely that you'd need more than 10 deg nose low, with full throttle to regain airspeed. Once you can eliminate the bad gauge from your scan. The flying is easy. Heck, I can still remember a few simple power settings. Right around 2500 pph on the fuel flow, at about 5000' will give me about 240-250 kias in the Tomcat, straight and level. No need to panic. If you're engaging Autopilot so low to the ground that impact is imminent, then you're engaging autopilot too soon.

A bad gauge is no excuse to kill 71 people. I hope there's more to this story.

a reply to: cosmania

Could be looking at a scenario where along with airspeed indicator they lost reliable VSI, altitude, and attitude indicator, etc, too with the air data sensor(s) iced. Whiteout in the cloud, below it low vis conditions and the sky and ground are all shades of whites and greys. Could become a very bad time quite quickly.
Maybe trying to troubleshoot the problem instead of concentrating on flying the plane by analog instruments first.

a reply to: cosmania

It's not the first one by any means. When they started seeing the pitot tube failures on Airbus aircraft they had several close calls, and a frozen pitot tube played a role in AF447.

Pilot error they are saying on PPrune due to the Pitot ice up..Has happened before to a lot of aircraft over the years.Pilot training is what makes the malfunction either a fatal crash or a recovery.

According to the timeline being given:

Aircraft took off at 1421. Autopilot was engaged between 430-490 feet, flaps were retracted around 1800 feet.

At around 2:30 after takeoff, as they neared 4300 feet, a difference in speed appeared between the captain's air data system and a backup. There's no reading on the First Officer's system. There was no difference in altitude.

Twenty five seconds later they received a comparison warning, with the system showing 16 kts higher on the captain's side.

At 6500 feet there was another warning, this time the backup was higher than the captain's system, which was dropping.

The captain's system eventually reached 0, while the backup showed 290-300 kts.

They eventually went into the fatal dive, and reached 430 kts at impact. They were 30 degrees nose low, in a 25 degree right bank, with the captain's airspeed showing 0.

www.flightglobal.com...

originally posted by: Zaphod58
Initial indications from the FDR are that the crew was dealing with incorrect airspeed indications, most likely caused by icing on the pitot tubes.

www.rt.com...

Experts from the Ukraine are waiting to head to Russia to assist with the investigation, and the US has offered to assist as well.

Yeah, the news said the pilots didn't turn on the heaters, I'm a noob so have no idea what that means.

But would that make the plane blow up in a fireball?

Seems like if that would be the consequence, that would be at the top of the check list.

Totally sucks tho.

a reply to: burgerbuddy

There was no explosion until they hit the ground.

originally posted by: GBP/JPY
a reply to: Zaphod58God love em.....

Died doing what they loved, huh

would the A-148 have inertial separators...idk....curious does a turbofan just crunch through ice chunks breaking off the cowling....an ice chunk hit in London on camera yesterday....just curious bout that

Turbofans on aircraft don't have inertial separators, which are found on some ground based gas turbines. They are used mainly to divert small particulates which are not commonly found at altitude. And cowlings on jets are fitted with anti-ice systems to keep ice from ever forming, as opposed to "deicing" systems, which gets rid of ice that has already formed. An anti-ice system takes hot bleed air from the compressor section of the engine core and sends it to various area to keep them so hot that ice won't form. Some aircraft also use bleed air to keep windshields clear, although continuous use can weaken the windshield material.

The Gromov Flight Research Institute plans to fly an An-148 stimulating the takeoff of the accident aircraft. They'll fly with various systems switched off, attempting to recreate what happened in the crash.

tass.com...

Not necessarily related, but an interesting article came out today about airspeed indicator issues on the Sukhoi Superjet. In two days of heavy snowfall in Moscow, there were seven reports of unreliable airspeed indications. Since 2011, there have been 14 events reported.

www.flightglobal.com...