More fun flying The Predator.

Thank you Charles.

Thank you Charles.

The static line to rear may be blocked. Since you installed it at airport level it will read low at any altitude above that. Does it feed a rear altimeter too?

smiles,
Charles

The static system is hooked up to both air speed indicators and both altimeters Charles.

The static system consists of a static port on each side with a line connecting them under the front seat. One line goes forward to the front panel and one goes aft to the rear panel.

The altimeters match nicely. It is only the airspeed indicators that are in disagreement.

I looked for a picture that showed the hook up of hoses and these two are the best.

The static ports connect under the seat and the pitot is teed off before it reaches the front panel ASI and goes directly to the rear panel ASI.
 

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Confirm there is tube connected to the bottom of the tee.
 

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Thank you Jeff.

Thank you Jeff.

Confirm there is tube connected to the bottom of the tee.

All he lines are connected.

Pitot tube is connected to both air speed indicators.

Static ports are connected to each other, to both air speed indicators and both altimeters.

There are no leaks that I can find.

I may not be understanding your question.
 
Check that the rate-of-change is the same for both altimeters.

smiles,
Charles
 
Vance,
Try disconnecting the static air on the back seat air speed. If the two instruments
Read close, then you must have some sort of static supply problem to the rear.

Dave
 
Vance, you say the static ports are connected. I'm certainly no expert but I don't think they're supposed to be. I believe the air from the front pitot should go out one static port, and the air from the other pitot should go out the other static port.
 
Thank you Charles.

Thank you Charles.

Check that the rate-of-change is the same for both altimeters.

smiles,
Charles

How would I check that the rate of change is the same for both altimeters?
 
Thank you Dave.

Thank you Dave.

Vance,
Try disconnecting the static air on the back seat air speed. If the two instruments
Read close, then you must have some sort of static supply problem to the rear.

Dave

Good suggestion Dave, I will try it.

It is hard to make progress because I can't fly her from the back seat without someone in the front seat so I have to work with someone who is willing to fly with me.
 
Thank you Ed.

Thank you Ed.

Vance, you say the static ports are connected. I'm certainly no expert but I don't think they're supposed to be. I believe the air from the front pitot should go out one static port, and the air from the other pitot should go out the other static port.

We have a divergence of opinion Ed.

In my opinion the static ports are to give a reliable reference for altimeter, indicated airspeed, vertical speed indicator and transponder.

For example the indicated air speed is referencing the static pressure under those atmospheric conditions against the impact pressure from the pitot tube.

Getting the reference from behind the panel starts with low pressure so it doesn’t work very well. I have flown gyroplanes that the faster you fly the more optimistic the indicated air speed is because of the low pressure behind the windshield where they are getting the static presure.

The Predator has a static port on each side so if is flying uncoordinated it compensates with one port seeing low pressure and one seeing high pressure. In my opinion to make this work the static ports need to be connected together.
 
How would I check that the rate of change is the same for both altimeters?

Steep climb or dive and have front seat call speeds and see if back lags.

smiles,
Charles
 
Thank you Charles.

Thank you Charles.

Steep climb or dive and have front seat call speeds and see if back lags.

smiles,
Charles

I don’t know how big a variance is too much or how steep a climb is necessary.

During normal climb out the altimeters appear identical.

I watch them both on climb out in the early phases so I can remind the client to begin reducing power as we reach 50 feet below pattern altitude. I can’t read the Kollsman window from the back so on the first lap I cross check the altimeters to see that the client has properly set the altimeter. I find there are many ways to interpret the altimeter setting from the ATIS.

I will try to find someone to fly with me and call the altitudes out during a steep descent.
 
The surgical tubing we talked about will give the same results with out envolving the static system into the equation.

Clamping off the end of the surgical tubing and rolling it up will increase the pressure in the tube and result in the airspeed increasing. Roll off the tubing when reducing the airspeed instead of dumping the pressure to project the internal mechanisms.
 
Vance

Take it to someone that does aircraft pitot static tests and have them put their test box on it. That will find the problem.....
 
Thank you Jeff.

Thank you Jeff.

The surgical tubing we talked about will give the same results with out envolving the static system into the equation.

Clamping off the end of the surgical tubing and rolling it up will increase the pressure in the tube and result in the airspeed increasing. Roll off the tubing when reducing the airspeed instead of dumping the pressure to project the internal mechanisms.

I just haven’t had time to run it down the road.

It has been down to 32 degrees F here and I have had a hard time launching when I don’t have a client.

I have a client coming tomorrow that is usually late. I will try to get it done and let you all know what I find out.

If Phil at Coastal Valley Aviation is available I am going to try Mark’s suggestion too.

Things tend to get chaotic this time of year.
 
Good suggestion Mark, thank you.

Good suggestion Mark, thank you.

Vance

Take it to someone that does aircraft pitot static tests and have them put their test box on it. That will find the problem.....

If Phil at Coastal Valley is not available I am going to try Jeff's suggestion.

I feel a proper tester will give me more and better information so if I can get Phil's attention I will check it with a test unit.

I will post what I find out here when I get it done.

The hanger is not a fun place to be when it is close to freezing so i have been slow to get her tested.
 
If Phil at Coastal Valley is not available I am going to try Jeff's suggestion.

I feel a proper tester will give me more and better information so if I can get Phil's attention I will check it with a test unit.

I will post what I find out here when I get it done.

The hanger is not a fun place to be when it is close to freezing so i have been slow to get her tested.

Cool... Hope it's a simple fix......
 
The cold has me slowed down a little.

The cold has me slowed down a little.

I just spoke with Phil at Coastal Valley Aviation and he is going to look into the IAS error tomorrow, December 22. I have been having a hard time coordinating with him.

I haven’t had a chance to pick up the tubing as Jeff Tipton suggested.

The cold has me slowed down a little although it is 61 degrees F now it is supposed to get into the low 40s tonight.
 
That didn’t work out.

That didn’t work out.

I launched later than expected and Phil went home early yesterday. He does not appear to be open today.

Light rain and gusting winds will keep me at home today.

I don’t know when Phil will be back.

I will let you all know what I find out.

Tomorrow doesn’t look good for flying either.

I hope to go flying Sunday, December 25.

Merry Christmas!
 
What happens when it rains?

What happens when it rains?

I get wet.

It was supposed to be blustery and windy all day so I planned to do things other than fly.

I looked out the window at the Santa Maria Valley at 11:00 and the leaves on the trees weren’t blowing hard and the sky was a lovely blue with fluffy white clouds. I checked the weather and the forecast and it appeared to be a lovely day to fly to San Luis Obispo for lunch.

I had not flown the Predator from the front seat in the last 41 days so waiting till tomorrow seemed like a bad idea. Tomorrow is promised to no one.

It was almost noon by the time I made it to SMX.

I called Leidos and the very friendly weather briefer cautioned me to stay low. Freezing levels were 2,000 feet and there were some cumulonimbus clouds popping up.

Precipitation was unlikely.

I worked through a careful preflight and pushed The Predator outside.

I checked the ATIS and winds were 270 degrees at 14kts gusting to 20kts.

I have never heard ATC speak so fast. I am glad he doesn’t do it with my clients. There were very few pilots to talk to so I don’t understand his need for speed.

The run up went well, I changed from ground to tower, turned the transponder to mode C.

I heard the magic words; “experimental gyroplane 142 Mike Golf; straight out approved; runway 30 clear for takeoff.”

We were wheels up by 12:15.

I went through my pre-rotator and takeoff instructions aloud and followed them well.

I was a little slow to add power and The Predator leapt into the air at 55kts as soon as I advanced the throttle.

It is hard to understand the trouble my clients have keeping the nose down.

There were dark shadows and when I would emerge from one I could feel the warm sun on my face. I love the sensory overload I get flying The Predator.

The throttle was moving constantly as the building clouds tried to suck us up and the nearby down drafts would cause a sink. Level required anywhere from 1,800 engine rpm to 2,320 rpm. I loved the challenge of straight and level.

The recent rains are turning the hills a rich green and I love the smell of the wet earth.

My microphone muff does not work as well in the front seat and I had some wind noise.

I called San Luis Obispo ATC from eleven miles to the south east, inbound with Zulu. He asked me if I wanted direct or a left downwind for runway two niner. I had already told him I wanted to come in through the Avilla pass (left downwind for two niner) so I tried to put it in his words.

“Experimental two Mike Golf, make left traffic for runway two niner; report midfield.”

I dutifully read back the instructions.

Over Shell beach he asked me my position and altitude and again in the Avilla pass. The only traffic was coming from the north plus someone working left closed traffic.

When I reported left downwind for runway two niner to land he gave me two wind checks as I made my way toward the ground.

Apparently I was not to too rusty because the landing was one of those where I wonder if I have touched down.

“Experimental 142 Mike Golf taxi to parking; remain this frequency.”

I was the only aircraft in restaurant parking and no one was on the patio. I was concerned the Spirit of San Luis was closed.

It was not and both the owners were there treating my like an honored guest.

I ate inside the heated restaurant and was slow to depart.

I felt a single drop of rain during my preflight that was quickly joined my many more. It was pouring as I taxied to self-serve.

The fast moving rain storm passed as I was filling up but had some friends behind peaking over the mountains.

ATC launched me with a helicopter less than a mile out.

“Experimental 142 Mike Golf, I have lost sight of you in the rain; would you please let me know when you are clear of my Delta?

I climbed out quickly at 75kts indicated air speed making 95kts of ground speed. I was getting sucked up into the clouds so I backed way off the power when I reached 1,200 feet.

I was looking for some blue sky and found it over the Oceano Dunes. I was surprised to see BB sized hail bouncing off my kneeboard. The nearest cloud was 15 miles away.

I called Santa Maria Tower and I was to make right traffic for runway 30 and report midfield.

That took me right through what appeared to be rain but when I got there is was dry.

The landing was as nice as could be and ATC wished me a Merry Christmas.

No pictures from the flight home because my camera is not waterproof.

I pushed her into the hangar just before the skies opened up and drove home in a pouring rain.

Average speed was 46kts for the 58 nautical mile flight (44kts direct) with a maximum ground speed of 96kts.

What a great way to spend a few hours on the day before Christmas!

Merry Christmas to all!
 

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Now that sounds like a great Christmas Day. Happy Christmas Vance.
 
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