B-17 from the Liddard family..

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retiredVTT
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B-17 from the Liddard family..

Unread post by retiredVTT » Mon Jul 02, 2012 1:39 pm

The maiden flight was performed by John L. today with the four engines beating out a unique sound of their own.

A lot was learned about flaps today....number one is that they sure get you airborne quickly...almost to the point of propelling the plane vertically into a stall....and number two is that one is supposed to retract the flaps after takeoff...!

With the flaps deployed for the entire flight, John had his hands full, as I tried to crank in gobs of down elevator to level the flight.

After what seemed like five minutes of fighting the beast, (it was probably three minutes tops) it was decided to land and what do you know,,with those flaps still hanging down, the big rig lumbered in and sat herself down just fine...!

Cudos to John for hanging in with the beast, through a difficult few minutes, a lesser pilot might have bailed...!

It was the highlight of the morning..!

Bill
Bill
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MAAC #13708

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JohnOSullivan
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Re: B-17 from the Liddard family..

Unread post by JohnOSullivan » Mon Jul 02, 2012 2:02 pm

Certainly had a high pucker factor. watching from the sidelines there were some comments on the first few minutes - Definitely responded like rearward CG issues. This was not the case!
Not discovered until after a beautifully smooth landing, was that that flaps were deployed throughout the whole flight.
Flaps can be a boon, but flaps, without down elevator compensation, just lead to ballooning and oscillating flight.
Deploying flaps essentially makes a highly cambered wing airfoil with lots of lift. this requires input of significant down elevator to compensate.
However, during the flight John and Bill had the sense to feed in lots of down elevator and saved the day.
John
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waxman
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Re: B-17 from the Liddard family..

Unread post by waxman » Tue Jul 03, 2012 11:50 pm

Thanks everyone for all the support and round of cheers when we finally brought the big bird in. Bill was instrumental in helping me guide the B17 around, providing a third hand on the trims and lots of great coaching during it's perilous oscillations. I must say that seeing the B17 coming in for landing from my perspective on the field made all the "terror" worth while. It looked amazing coming at at about 5-6 ft in the air with all 4 engines turning as it finally descended to the ground. Landed without even a grass stain. Next time I'll try it without flaps. ;-)

John L
retiredVTT wrote:The maiden flight was performed by John L. today with the four engines beating out a unique sound of their own.

A lot was learned about flaps today....number one is that they sure get you airborne quickly...almost to the point of propelling the plane vertically into a stall....and number two is that one is supposed to retract the flaps after takeoff...!

With the flaps deployed for the entire flight, John had his hands full, as I tried to crank in gobs of down elevator to level the flight.

After what seemed like five minutes of fighting the beast, (it was probably three minutes tops) it was decided to land and what do you know,,with those flaps still hanging down, the big rig lumbered in and sat herself down just fine...!

Cudos to John for hanging in with the beast, through a difficult few minutes, a lesser pilot might have bailed...!

It was the highlight of the morning..!

Bill
John Liddard

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Coyote
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Re: B-17 from the Liddard family..

Unread post by Coyote » Wed Jul 04, 2012 5:58 am

Very glad everything went smoothly on landing

Having used flaps before, many actually do NOT use flaps on first flight (even retracts are sometimes left in down position until lots of height) unless you have to due to short runway like at SP.

As mentioned before flaps and retracts can make an aircraft balloon up or plummet downward - thus requirement for height when deployed/retracted for first time

Maidening a new aircraft is difficult enough without adding more problems ;)

Good safety tip and lesson learned here
-----------------------------------------------------
Marc "Coyote" Cayouette
Halifax Electric Flyers Association (HEFA) # 054
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waxman
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Re: B-17 from the Liddard family..

Unread post by waxman » Wed Jul 04, 2012 1:07 pm

Flaps were used intentionally to ensure enough lift for take off (as flaps are intended) as there was no familiarity with flight characteristics of this new model. Problem was, I simply forgot to retract them once I got into the air. They truly provided a benefit on the landing approach. Now that i know it flies the next take-off will be without flaps. Ah! The life of a test pilot :-)

John

Coyote wrote:Very glad everything went smoothly on landing

Having used flaps before, many actually do NOT use flaps on first flight (even retracts are sometimes left in down position until lots of height) unless you have to due to short runway like at SP.

As mentioned before flaps and retracts can make an aircraft balloon up or plummet downward - thus requirement for height when deployed/retracted for first time

Maidening a new aircraft is difficult enough without adding more problems ;)

Good safety tip and lesson learned here
John Liddard

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Coyote
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Re: B-17 from the Liddard family..

Unread post by Coyote » Wed Jul 04, 2012 6:44 pm

LOL John!

I kind of figured that's why flaps had been used - short runway and large model. She flew and made it down safely which is what counts.

Who said test pilots lived glamourous lives ;-)
-----------------------------------------------------
Marc "Coyote" Cayouette
Halifax Electric Flyers Association (HEFA) # 054
MAAC #35128
DX9

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yorcram
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Re: B-17 from the Liddard family..

Unread post by yorcram » Wed Jul 04, 2012 8:44 pm

Can't wait to see it fly. Gotta love scale planes.
Plane Crazey :D

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