BREAKING - B-17G bomber crashed near Hartford

[FLS]

No flaps/reduced flaps is the correct configuration with two of four in trouble.   Adding flaps would have put them in the weeds sooner.    The goal is to minimize drag until landing is assured. 

The power was likely reduced after they made the runway.   

I don't mean low power setting, I meant low power as indicated by the inability to climb or reach the runway.

I know flaps add drag but they add more lift than drag for typically the first 50% of extension. So obviously not landing flaps but a little flap extension might have helped. Just speculating, not criticizing the pilots.

[Vraciu]

I don't mean low power setting, I meant low power as indicated by the inability to climb or reach the runway.

I know flaps add drag but they add more lift than drag for typically the first 50% of extension. So obviously not landing flaps but a little flap extension might have helped. Just speculating, not c :mad:riticizing the pilots.

Flaps do not help in this situation.  Flaps add drag.  Saying they add more lift than drag for the first X percent of extension is a nice talking point (it borders on the dogmatic) but is overly simplistic--and not generally accurate.  Regardless, adding lift also creates drag.  Drag is the enemy in this circumstance.  You must get the airplane cleaned up and accelerated to the final segment speed in a jet or L/D Max in a piston (Vyse, etc.).  Flaps absolutely would not have helped in the emergency condition this airplane faced unless the goal was to land off-airport.

I have a ton of time in high performance piston twins like the Baron, 310, 340, 414, 421, etc. (as well those of lower performance like the Cougar and Seminole) and can think of nary a one where I wanted flaps out during an attempt to climb with an inoperative engine.  This airplane was in similarly dire straits.  Even with three good engines flaps would only be used when landing was assured, if at all.

As for power, I suspect they had the thing firewalled.  The issue wasn't power output, by my best guess, it was drag due to a windmilling prop or something along those lines.  See Busher's statement regarding the C-130.

[davidpt40]

I don't mean low power setting, I meant low power as indicated by the inability to climb or reach the runway.

I know flaps add drag but they add more lift than drag for typically the first 50% of extension. So obviously not landing flaps but a little flap extension might have helped. Just speculating, not criticizing the pilots.

You bring up an interesting point.  If both engines 3 and 4 were disabled (though I think Puma's idea of the prop simply feathering due to being torn off the wing is more likely), the pilot would have to keep the airspeed up.  Even with the giant vertical stabilizer the B-17 has, below a certain speed it can't handle the yaw of two engines being out on the same wing.

Both engines 3 and 4 were torn from the right wing.  One ended up in the deicing tank, another in the deicing building. 

[FLS]

... Even with three good engines flaps would only be used when landing was assured, if at all.
...

The communication with the tower sounded like they thought they had three good engines and would make the runway.

[Vraciu]

The communication with the tower sounded like they thought they had three good engines and would make the runway.

Well they were wrong, weren't they?  And they remained clean wing because that was what was required to make the runway.

A landing assured judgment in this case would not be made until VERY short final, buy which point configuring would violate stabilized approach criteria.  Land with what you have set is the general principle.  Changing the configuration down low can cause bad things to happen without sufficient altitude to recover.

[Mister Fork]

Vraciu - following Occam's razor approach, it would be easiest to surmise that they lost an engine and following Busher's point if you can't feather the engine because of a failure, you're now in a negative climb rate. 

Then it's just a math exercise. What's going against them?
1. The B-17 engines are as aerodynamic as a shoebox.
2. The B-17 airplane itself an aerodynamic model from the late 1930s
3. The aircraft was at 500'  and Altitude = Energy
4. Based on Busher's comment on the C-130, the B-17 had just 500' of energy to turn around, and re-line-up for final.

Unfortunately, the math didn't add up to a successful probable landing.

It does beg the question... these old birds... is it worth it to keep them flying like this knowing how vulnerable they are when things go wrong? Old design = little room for issues?

[Vraciu]

A fair assessment. 

As for risk, what's life without it?  I say fly them until they can't be flown any longer.   History is alive through these machines.   That's priceless in my view. 

[mikeWe9a]

Good question.  It's usually a series of things that cause an accident.  Wet magnetos were definitely a problem.  Maybe something malfunctioned on engine #3 also, at least on the prop controls.

Having one blade feathered isn't a prop control problem - the blades don't change pitch independently, but are all tied together with a large gear in the hub.  Either that gear or the base of the prop blade had to shear off the large interlocking teeth to allow that blade to twist out of alignment with the others.  I believe that the report stated that the feathered blade was broken off near the tip, so it is possible that the change in pitch happened after the blade struck something during the crash (approach light framework, etc.).

Mike

[Vraciu]

Having one blade feathered isn't a prop control problem - the blades don't change pitch independently, but are all tied together with a large gear in the hub.  Either that gear or the base of the prop blade had to shear off the large interlocking teeth to allow that blade to twist out of alignment with the others.  I believe that the report stated that the feathered blade was broken off near the tip, so it is possible that the change in pitch happened after the blade struck something during the crash (approach light framework, etc.).

Mike

This has been my thinking as well.   The one blade being out of synch with the other two has to be the result of the impact, not something that occurred in flight.   To be otherwise would mean something extremely remote.

[Wolfala]

Still can’t believe there is no video.

How’s the FE doing?   He may be the key to unraveling this one. 

I don’t think they have any solid decision on what No. 3 propeller was doing yet.

Thought experiment since we have a fairly completely modeled B-17 laying around doing nothing but getting shot up. Why not just can 2 engines at a sea level airport and see how it flies or doesn’t.

Then do another and can the #4 and roll back the #3 to idle. See what happens.

[Vraciu]

Thought experiment since we have a fairly completely modeled B-17 laying around doing nothing but getting shot up. Why not just can 2 engines at a sea level airport and see how it flies or doesn’t.

Then do another and can the #4 and roll back the #3 to idle. See what happens.

Not a bad idea just to see.   The accident airplane was probably a bit lighter than ours is, but still worth a shot.

Can we duplicate the weather conditions?

[Wolfala]

Not a bad idea just to see.   The accident airplane was probably a bit lighter than ours is, but still worth a shot.

Can we duplicate the weather conditions?

Bradley was pretty close to a standard day on that particular flight so I would just assume that whatever sandbox we use is going to be a standard day

[FLS]

Bradley elevation is 173 ft. I'm guessing 25% fuel might be a little heavier total weight.

[Mister Fork]

Not a bad idea just to see.   The accident airplane was probably a bit lighter than ours is, but still worth a shot.

Can we duplicate the weather conditions?

Temperature was 23°C (73°F) - the same as our engine environment. Wind was calm. 25% fuel load is a good equivalency. B-17 normal 100% load is 6435L (1700 gallons). They did add 605L of fuel (160 gallons) but it is not reported on what was already in the tanks.

[Vraciu]

Sounds good, guys.   Couldn't hurt to try it.