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Female Co-Pilot pulls up landing gear before take off :D

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It might look funny to us but we should pity the lady. Her hopes of flying are dashed altogether. Irrespective of the gender , working as ground crew subject to ridicules would be heart wrenching. As they say for space programs, failure is not an option.
 
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There's no weight sensor on the wheels? Seems like an easy way to screw up a plane sitting on the tarmac.
There are interlocks, mechanical and logical, that will not allow gear retraction when there is weight-on-wheels (WOW). When I said 'logical', it mean there is a WOW switch on each landing gear. The switch is a full mechanical device that activate an electrical -- on/off -- signal that tells other systems on the landing gear's condition, and by inference, the aircraft is on the ground with its full weight on all the landing gears.

An example of the WOW system is here...

G450 Landing Gear Weight on Wheels System

On the schematic, the WOW switches are represented on the left side.

You can see that even the fuel system want/need to know the aircraft's WOW condition to allow ground servicing -- refuel.

Nose landing gear WOW condition is necessary for nose wheel steering, as in NWS is not activated unless there is full WOW on the nose landing gear.

The spoilers and thrust reversers want/need to know main landing gear WOW condition. You certainly do not want spoilers and thrust reversers activation if you are still fully airborne.

That is why this story is incomplete. Not wrong. Just incomplete.

Watch this video of a MIG-29 gear retraction on take off...


At timestamp 0:03 the jet's nose lift, meaning there is no WOW on the nose gear.

At timestamp 0:05 and 0:06, the main gear began their retraction. Then a major boo-boo-owie happened.

Three possibilities, and each is technically legitimate. I do not mislead people here when it comes to technical issues.

ONE -- The MIG's landing gear system is flawed, as in having a design flaw. If there is any weight-ON-wheels on any landing gear, logical interlocks should prevent any landing gear movement. In other words, there must be weight-OFF-wheels on all three landing gears. This possibility is not to be insulting to the Russians. Everybody, including US, make and made design flaws.

I am not saying there is a design flaw in the MIG, only that a design flaw is a possibility in any mishap.

TWO -- There was a maintenance related issue where the pilot was misled by his own jet that it was safe to retract.

Here is an example...

Aviation Today :: Disabling The Weight On Wheels Switch
...maintenance performed...failed to remove tongue depressors that were being used to disable the weight-on-wheels (WOW) switch of a Gulfstream V on jacks. That practice led to a hard landing causing substantial damage to the airplane...
Basically, Maintenance simulated weight-OFF-wheels for whatever it was they needed to do when the jet was in their possession, but they forgot to remove the simple wooden thingie that simulated that landing gear condition when they returned the jet to Operations. So a major boo-boo-owie happened.

THREE -- Just because your aircraft tells you that there are weight-OFF-wheels on all landing gears, there is something call 'positive rate of climb' that must be there BEFORE you retract the landing gears.

Insights Positive climb, gear up - Flight Training
One of three techniques is normally taught for landing-gear retraction: when a landing on the runway is no longer possible; when the vertical speed indicator shows a positive rate of climb; or when a positive climb is evident while looking outside the cockpit.
The landing gear interlocks system have no knowledge of the positive rate of climb. That is YOUR responsibility.

YOU must increase throttle to create that positive rate of climb. If you did not, as you pitch up you will lose airspeed and if you retract the landing gear as you pitch up, a major boo-boo-owie will occur.

Going back to this event...

On an aircraft where the pilot does everything, like the MIG, it is the pilot that must make these observations, decisions, and execute. When I was on the F-16, just because there is a back seater (B/D models), that does not mean there is a division of labor and responsibilities between the front and rear seats. The front seat is the decision maker and executor.

On an aircraft where two pilots are designed in, as in captain and co-pilot, the pilot observes and decides, then orders the co-pilot to do some things. In other words, there are shared executions of actions. The pilot creates that positive rate of climb, make sure the aircraft obeyed and all conditions are satisfactory, then order the co-pilot to retract landing gears, raise flaps, etc. There is no need for the captain/pilot to do everything. The co-pilot is there to assist in flying, so let him/her be responsible for some tasks.

So for this event where even though the details are rather scant, I am willing to say that possibility one is out of the equation. The WOW concept and engineering is too matured for anyone to muck it up. That leave possibilities two and three.

Maintenance as the cause can be ruled out since the co-pilot was removed from flight duty. That leave possibility three as most probable.

An aircraft on a take off run can be deceiving in appearance. It may have complete weight-OFF-wheels but still appears to observers that it is still on the runway. So what likely happened was the co-pilot retracted the landing gear without pilot's order.
 
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reminded me of a Homer Simpson episode.

Where homer pretend to be a pilot to drink in a pub and got pulled in to fly an aircraft. He have been touching everything in the console and finally he lift the gear and the aircraft felt.

Funny tho, on Simpsons, he was compensated for making a fuzz to hush up the incident LOL :)
 
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Looks like I was wrong. On post 19, I said this...

The WOW concept and engineering is too matured for anyone to muck it up.

Source: Female Co-Pilot pulls up landing gear before take off :D | Page 2
Now that I saw a more detailed report, it said this...

Accident: Luxair DH8D at Saarbruecken on Sep 30th 2015, takeoff ending on belly, smoke in cabin
According to gear design logic the gear is going to retract as soon as the nose gear weight on wheel sensor indicates airborne, even if the main gear is still on the ground.
Sorry...But WTF ? Why would you want to design an aircraft that says 'airborne' when most of its weight is still on the ground ? I guess it is possible to muck it up.

Very interesting...Reading the various commentaries from other people, there is this...

I flew the Q400 for many years, but was never aware that the gear could retract with WOW. I am amazed that this is accepted as a certification standard and am very curious what the BFU final report recommendations will be.

Maybe if the pilots would have known this weakness in Dash gear logic,
the PNF would have been more vigilant preventing the 'brain fart'. Dash pilots are already vigilant as it comes to gear, we are trained never to revert a gear selection as MightyQ suggests. How come this weakness was not known among Q400 pilots?

If it would have been an other type of aircraft this accident would not have been possible, or if the gear would have been commanded up 2 seconds later the incident would not even have been report worthy. This shows that any short coming in aircraft design will eventually come to surface and does not need a bad pilot at the controls.
Unbelievable...!!! So there was a landing gear WOW design flaw.
 
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There are interlocks, mechanical and logical, that will not allow gear retraction when there is weight-on-wheels (WOW). When I said 'logical', it mean there is a WOW switch on each landing gear. The switch is a full mechanical device that activate an electrical -- on/off -- signal that tells other systems on the landing gear's condition, and by inference, the aircraft is on the ground with its full weight on all the landing gears.

An example of the WOW system is here...

G450 Landing Gear Weight on Wheels System

On the schematic, the WOW switches are represented on the left side.

You can see that even the fuel system want/need to know the aircraft's WOW condition to allow ground servicing -- refuel.

Nose landing gear WOW condition is necessary for nose wheel steering, as in NWS is not activated unless there is full WOW on the nose landing gear.

The spoilers and thrust reversers want/need to know main landing gear WOW condition. You certainly do not want spoilers and thrust reversers activation if you are still fully airborne.

That is why this story is incomplete. Not wrong. Just incomplete.

Watch this video of a MIG-29 gear retraction on take off...


At timestamp 0:03 the jet's nose lift, meaning there is no WOW on the nose gear.

At timestamp 0:05 and 0:06, the main gear began their retraction. Then a major boo-boo-owie happened.

Three possibilities, and each is technically legitimate. I do not mislead people here when it comes to technical issues.

ONE -- The MIG's landing gear system is flawed, as in having a design flaw. If there is any weight-ON-wheels on any landing gear, logical interlocks should prevent any landing gear movement. In other words, there must be weight-OFF-wheels on all three landing gears. This possibility is not to be insulting to the Russians. Everybody, including US, make and made design flaws.

I am not saying there is a design flaw in the MIG, only that a design flaw is a possibility in any mishap.

TWO -- There was a maintenance related issue where the pilot was misled by his own jet that it was safe to retract.

Here is an example...

Aviation Today :: Disabling The Weight On Wheels Switch

Basically, Maintenance simulated weight-OFF-wheels for whatever it was they needed to do when the jet was in their possession, but they forgot to remove the simple wooden thingie that simulated that landing gear condition when they returned the jet to Operations. So a major boo-boo-owie happened.

THREE -- Just because your aircraft tells you that there are weight-OFF-wheels on all landing gears, there is something call 'positive rate of climb' that must be there BEFORE you retract the landing gears.

Insights Positive climb, gear up - Flight Training

The landing gear interlocks system have no knowledge of the positive rate of climb. That is YOUR responsibility.

YOU must increase throttle to create that positive rate of climb. If you did not, as you pitch up you will lose airspeed and if you retract the landing gear as you pitch up, a major boo-boo-owie will occur.

Going back to this event...

On an aircraft where the pilot does everything, like the MIG, it is the pilot that must make these observations, decisions, and execute. When I was on the F-16, just because there is a back seater (B/D models), that does not mean there is a division of labor and responsibilities between the front and rear seats. The front seat is the decision maker and executor.

On an aircraft where two pilots are designed in, as in captain and co-pilot, the pilot observes and decides, then orders the co-pilot to do some things. In other words, there are shared executions of actions. The pilot creates that positive rate of climb, make sure the aircraft obeyed and all conditions are satisfactory, then order the co-pilot to retract landing gears, raise flaps, etc. There is no need for the captain/pilot to do everything. The co-pilot is there to assist in flying, so let him/her be responsible for some tasks.

So for this event where even though the details are rather scant, I am willing to say that possibility one is out of the equation. The WOW concept and engineering is too matured for anyone to muck it up. That leave possibilities two and three.

Maintenance as the cause can be ruled out since the co-pilot was removed from flight duty. That leave possibility three as most probable.

An aircraft on a take off run can be deceiving in appearance. It may have complete weight-OFF-wheels but still appears to observers that it is still on the runway. So what likely happened was the co-pilot retracted the landing gear without pilot's order.

I expected there must be some kind of mechanical way of preventing such a silly accident. However it didn't occur to me that maybe on some planes it is only on the front wheel. So yes the front wheel could be off the ground yet the rears still on the ground..and bad things can happen.

I think the pilot must have turned to the co-pilot to say something and she just by procedural habit just assumed he was going to say "gear up" and she immediately threw the switch. doh!!

Sorry...But WTF ? Why would you want to design an aircraft that says 'airborne' when most of its weight is still on the ground ? I guess it is possible to muck it up.

That does seem pretty stupid. At least put it on the rears instead.
 
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