Hanger Flying/ I learned from this experience

At 15:55 09 April 2015, Jonathan St. Cloud wrote:
How did you know the TE was disconnected? My first thought would be
the vario does not work right, I would think it would be a process
involving
several flights and much frustration to find out the TE was disconnected?

Well since you ask -

It was a Duo. It was very obvious that the 302 vario had defective total

energy over the first few flights. There was no visible defect in the
tubing
or TE probe but when I sucked on the TE tube at the instrument end with
the TE tube outlets blocked it was obvious that there was a major leak. We

blew an air supply down the tube while I listened with a stethoscope down
the length of the fuselage and fin which told us only that it was from
somewhere in the fin area. I borrowed an old medical endoscope and we
introduced it through the elevator rod hole in the top of the fin could see
the
tube was completely detached from the fin fitting. The tricky bit was
getting
a photograph to prove it to the agent and factory so as to get the fin hole

and repair done under warranty as there was no direct line of sight - that

took an angled dentist's mirror in the fin, a camera peering into it and a
lot
of trial and error.

All three tubes were held on to the triple probe fitting by tie wraps which
are
worse than useless for that purpose.

John Galloway

On 4/9/2015 9:17 AM, Steve Leonard wrote:
On Thursday, April 9, 2015 at 9:46:26 AM UTC-5, Mike the Strike wrote:
I had a similar experience with a 20 year-old ASW-20. The previous owner
had installed lead weights in the tail and wings without any logbook
notation and the weight and balance was far off (aft of permitted). On
one of my first flights, I eased back into a thermal and suddenly found
myself looking upwards at blue sky!

I always do a weight and balance on new ships now!

Mike

And even if you don't have a scale capable of the weight on the main, at
least you can check the weight on the tail. If you look at W&B numbers,
you can see that the weight on the main has a relatively small impact on
the CG location. Being off on that weight by 20 or 30 lbs has a smaller
effect on the CG than being off by 2 or 3 lbs on the tail weight. If the
tail weight is close to what is recorded at the most recent W&B, odds are
you can get a good handle on where your flight CG will be with you on
board. If not, well, you better get a bigger scale to be able to check the
whole plane!

Steve Leonard


Heh! It took me - with George Applebay's help - 7 or 8 years to learn the 7
pounds of lead shown in my ship's build log/most-recent-W&B as being installed
in the aft fin was because the original owner weighed about 100 lb more than
my 140 pounds, and George wanted the CG "OK for the heavy guy." I'd never
bothered to do the arithmetic for me, being OK with "Kentucky windage" and
rationalization. Got away with it, too, though the embarrassment felt like it
might kill me.

I'd been flying "considerably aft" of George's defined limit for all that
time, and the fact that - once things were properly redone for my weight - I
could detect no change in flying qualities was scant comfort.

My rationale at the time was the recently-been-flown ship had only 30 hours on
it, so how far off could the CG be? (Ha ha ha! What an idiot I was. Pretty
damn far!)

Bob - Kids, it may be significant lotsa people have chimed in w. CG horror
stories - W.

On Thursday, April 9, 2015 at 12:36:13 AM UTC-6, Jonathan St. Cloud wrote:
In the war bird community we had hangar flying sessions where we talked about the emergencies we experienced and how we handled them. These were priceless sessions! I learned what other pilots did in situations I had never thought of. So here is my first post about something that taught me a lesson. Hopefully others will share their experiences too. This should be a judgment free thread for learning and sharing.

Here is something that taught me about flying. I had purchased a brand new Ventus 2C (I think it was 2000 or 2001). As part of the options I had the CG adjusted for pilot weight at the factory. When my shinny new glider arrived I was keen to get it in the air. My first big mistake was to trust the factory W&B! I had never flown an aircraft out of the CG range except once when a passenger lied to me about their weight (by 60 Lbs) while flying a helicopter. I ran out of aft stick on landing, not a big event on a paved runway. Anyway back to my story. My plan as always with a new (to me) glider was to take a high tow, do a few turns and stall or two, I was even planning on a spin. Well on tow I noticed my new glider (first and only time I purchased a new glider) was rather pitch sensitive, off tow, it was all I could do to keep it between 45 knots and 75 knots. Fortunately, the day was booming so staying up was not too difficult. I immediately abandoned my plan of some turns, stalls and maybe a spin. I thought the problem was with me as I had not been flying fixed wing aircraft much in the prior two years. I flew for four hours, got a bit better controlling the speed. I entered the pattern about 4,000 AGL and practised flying the pattern keeping my speed to within as small a speed deviation as I could. After landing I thought the problem was with me and possibly the brand as I had heard the first Ventus' were not known to be easy to fly. I thought nothing more than I need a bunch more time in this glider and never even mentioned my speed control problems to my fellow pilots as I was too embarassed. I put about 20 hours on that glider in two months and even had a few notable interesting XC flights. With time I got much better at the speed control (used to fly an all flying tail glider), but I never felt comfortable. Finally I confessed my experiences to another pilot and that I thought somehow I could not fly fixed wing aircraft anymore. Well, this pilot mentioned that it sounded like a CG problem. That had never occurred to me, nor did I have any experience in this area. Looked at the aircraft logbook again and had a W&B done. The logs and W&B calculations done by the factory showed I need 11 lbs of tail weight, the weight from the factory in the tail was 11 kilograms!!! I seem to remember NASA losing a Mars lander with JPL using metric calculations and NASA using English system

What did I learn: 1) Always perform a W&B on a glider that is new to you; 2) Never be shy about admitting your flying problems to fellow pilots; 3) do not plan to perform stalls and spins on the very first flight; 4) do not make excuses for the glider or how it is flying or how you are flying it, tell someone about it!

Maybe someone else could add a few comments about what they would have done and anything else I could learn from this. Also, share your own story so we might all learn.

Not really glider related but it could be.

Once, long ago, I was chugging across Oklahoma in a J3 Cub with about 70mph on the ASI. Then I noticed the airspeed acting "funny". Climb and the airspeed went up, dive and it went down - the exact opposite of what I'd been taught to expect. I had a couple of hours to go on the XC so I decided to ignore it for now - known power at a known pitch attitude would produce an airspeed close to what I wanted. Anyway, I knew a good mechanic at my destination.

Having not much else to do except navigate by road signs 1,000' below and town names on water towers, I started working out what my ASI problem was. I settled on a probable plugged pitot tube with the 'capacity' in the tubing leading to the panel making the ASI act like a rate of climb instrument.

Sure enough, when the mechanic heard the problem described, he nodded, reached under the Cub's panel to remove the rubber tube from the back of the ASI and using his compressed air blow-off gun blasted the pitot clear. Seems I had taken a bug-strike directly on the pitot and the remains had congealed into a solid plug.

Critters always make good hangar stories. Small furry ones like to nest in gliders and long slithery ones go in after them. But, that's another story.

On Thursday, April 9, 2015 at 10:46:26 AM UTC-4, Mike the Strike wrote:
I had a similar experience with a 20 year-old ASW-20. The previous owner had installed lead weights in the tail and wings without any logbook notation and the weight and balance was far off (aft of permitted). On one of my first flights, I eased back into a thermal and suddenly found myself looking upwards at blue sky!

I always do a weight and balance on new ships now!

Mike

CG issues seem to be "in the vane" for this thread.

It was an ASW-20C with "Nixon winglets".
Owned by my family for a number of years.
CG had been worked out (properly) and "tail ballasted" for one owner (who outweighed me by ~80lbs)(?)so that the normal CG was ~90% aft.
I used the "OEM lead disc's" in the nose, I believe it was 5.

[If you've ever done the lead disc's in a '20, you know they're a bit of a PITA to see/reach up in the nose]

I had quite a few hours in our older '20A as well as this '20C.
We had a "low time glass pilot" (one of our towpilots, he had lots of airplane time) also fly the '20 and he was heavy (maybe 100lbs more than me). We had him fly my ballast to keep the CG more forward. Good thought for us, a bit safer for him.

One day, he decided to move the CG aft just to "try it out". He removed a disc or 2 and flew.
Later on, I was going to fly and decided to try the CG "a wee bit further aft", so I removed a disc (hey kids, see where this is going?!?!).
TO & tow were "OK", general flying was a bit twitchy.
I then did a "cruise to thermal zoomie" and promptly did an "over the top" spin entry (glad I was a few thousand feet up!) followed by a recovery.
The owner was towing and got to watch me & my antics.
I did another zoomie with the same results (again seen by the owner while towing) which prompted a radio call from him of, "Spin much Chuck?!?!".

I backed off a bit on what I did (since I was now current in '20 spin recovery), was very mindful of pattern speed and had a nice landing.
We checked things out (on the ground) and that's when we figured out what happened.
I was "quite a bit aft" of the aft limit.

Moral...... "Don't ASSUME, check & verify"!

Happened to another pilot I know (he has since left flying for medical reasons). He had a brand new ASW-27 and on, I believe it was his first flight, as he was coming in to land the airspeed was showing ever increasing speed.. He chased the airspeed just a bit and then thought he was flying fast enough. He held a steady pitch attitude and landed. After coming to a complete stop he was still showing airspeed. Tracked it down to a static tube from the airspeed was getting kinked when he closed the canopy which is why it was not affecting his altimeter too.

I had another experience where I took off in a glider with only 90 degree flaps for glide path control. I was a very low time pilot and still figuring out the "pilot thing", not that I have it figured out now. For those that have not flown a 90 degree flapped ship, I was taught to put in the flaps at a steady pace as pitched to an attitude (standing on the rudder pedals) then check the airspeed, because if you did not pitch down you might lose your airspeed and never get it back. Well I took off and did not check my airspeed until I was on tow in the air. I had no airspeed indication (pitot was unplugged during maintenance). I landed fast going very fast as I did not want to stall.

Lesson learned. I always check my airspeed is "alive" while accelerating on the ground. This is actually part of any powered aircraft takeoff "airspeed alive...rotation speed". Second lesson learned was when a ship comes back from maintenance do a very careful and through preflight. At one point in my life I was flying a big complex cabin class pressurized twin. I always flew it to the maintenance shop, but I NEVER picked it up, they had to fly it to me after maintenance. Kind of like the parachute rigger than has to jump with the chutes he repacks.

New gliders can be especially exciting.

A few years back I was lurking about preparing to go fly,
when a guy landed back early after his first flight in his
just-off- the-boat supership, in a huge huff. He ran at me
yelling "Your damn instruments don't work. Now go fly that thing
and figure out what's wrong". Oooyyyy, I've heard this
before, and its not my stuff that's the problem ;-)

I strapped in and noticed the ASI reading 0 as I lifted off.
Had a lovely afternoon soaring in this gorgeous new machine,
gotta love that new-paint smell.
Without working instruments of course.
On landing still irate owner ran up to the glider (thought
I'd given him enough time to cool off). I popped the canopy
and pointed at the ASI - now indicating 50 knots.

There was about a quart of water in the static lines
and various other silliness. He hadn't washed it (literally
opened the trailer, got the paperwork, and flew).
Best guess is final wash at the factory?
I'm not sure how that much water can get in the statics.

I've also seen (not recently) logbooks recording test flights
that obviously never happened.

Take special care around new machines!

Hope that is helpful,
Best Regards, Dave

On Thursday, April 9, 2015 at 5:50:24 PM UTC-4, Dave Nadler wrote:
New gliders can be especially exciting.

A few years back I was lurking about preparing to go fly,
when a guy landed back early after his first flight in his
just-off- the-boat supership, in a huge huff. He ran at me
yelling "Your damn instruments don't work. Now go fly that thing
and figure out what's wrong". Oooyyyy, I've heard this
before, and its not my stuff that's the problem ;-)

I strapped in and noticed the ASI reading 0 as I lifted off.
Had a lovely afternoon soaring in this gorgeous new machine,
gotta love that new-paint smell.
Without working instruments of course.
On landing still irate owner ran up to the glider (thought
I'd given him enough time to cool off). I popped the canopy
and pointed at the ASI - now indicating 50 knots.

There was about a quart of water in the static lines
and various other silliness. He hadn't washed it (literally
opened the trailer, got the paperwork, and flew).
Best guess is final wash at the factory?
I'm not sure how that much water can get in the statics.

I've also seen (not recently) logbooks recording test flights
that obviously never happened.

Take special care around new machines!

Hope that is helpful,
Best Regards, Dave

"Spring 1st flight", did the "puff on the TE probe" to make sure instruments worked.....

Yes they did, until 3/4 of the way down the runway where I was flying and the AS showed a much lower value.......

Either.....
-Tubes were gnawed by rodents over the winter (could take a puff, not a steady pressure stream)
-TE probe (swapped between multiple sailplanes) was not seated, thus a leak

Results on both, "What does it sounds like, what does it feel like?"
Fly the frikkin plane, resolve "stupid issues" later on.

Multiple cases yielded a multi hour (not efficient) soaring flight......

There was a DG 800 motor glider that was delivered and crashed on its first flight on approach at the local airport. The elevator pushrod disconnected at the pivot horn at the base of the vertical fin. There was nothing locking the nut in place. Determined to be a factory defect in manufacturing.

BillT

On Thursday, April 9, 2015 at 8:36:19 PM UTC-7, Bill T wrote:
There was a DG 800 motor glider that was delivered and crashed on its first flight on approach at the local airport. The elevator pushrod disconnected at the pivot horn at the base of the vertical fin. There was nothing locking the nut in place. Determined to be a factory defect in manufacturing.

BillT

Years ago, I stupidly drilled through my rudder cable when installing a boom mike. When we removed the cable to replace it, we discovered that the factory had drilled through it about a foot further back, breaking about 40% of the strands.

Mike