Thread Tools
Sep 18, 2019, 08:31 AM
Registered User
Quote:
Originally Posted by Go4it
Now, this is just a wild guess. But, I had a jet about 5 years ago are so. Where the plastic tube was leaking air. You might check they always seem to fit at the top but some times it has a gap at the bottom causing leakage.
On my flexjet I had a devil of a time to make it fit like it came out. My hand was too big to shove it down the air tunnel so I had my wife help me get the plastic to fit all the way around the fan housing.

Checked, its perfect.
Sign up now
to remove ads between posts
Sep 18, 2019, 10:13 AM
Registered User
Quote:
Originally Posted by foundryratjim
Finally my spare time and weather cooperated. I had a fresh charged 6 cell Roaring top 70c 5500 pack ready to go. Ranged check done, verified control surface and flight mode operation.Verified my Jeti telemetry was talking to my transmitter. All is good. Position on runway ,started timer and gave her full throttle. She went straight down the runway for about 300 feet and didn't even get light on the nose even with high rates from the expert program. I stood in front of it to hold it and gave it full throttle. The telemetry said about 85 amps. Put it back on the flight stand and installed another fresh battery, full throttle peaked about 90 amps and leveled to 85. My throttle stick shows 100% travel on my radio. Any suggestions?
Had a similar thing initially. Two things, first are you taking off of a grass runway, geotex, pavement? Second, CG is critical I find with jets and EDF. Did you verify the CG position? Nose heavy makes it tough to initiate the rotation

If you are taking off of grass and CG is correct, keep light up elevator pressure on the roll to help unload the nose wheel and allow speed to come up and ease more up elevator in to lift off. Again if your plane is nose heavy you need t correct that first
Sep 18, 2019, 10:16 AM
Registered User
Quote:
Originally Posted by foundryratjim
Checked, its perfect.
Just noticed you od says your from Burt. There are quite a few guys in your area that fly EDF's & Turbines that I am sure would be willing to help also. Are you familar with any people in the Chesaning Club?
Sep 18, 2019, 11:12 AM
Registered User
Quote:
Originally Posted by rocket_33
Just noticed you od says your from Burt. There are quite a few guys in your area that fly EDF's & Turbines that I am sure would be willing to help also. Are you familar with any people in the Chesaning Club?
I have been a member almost from the beginning. I am currently the Treasurer. They all only fly off of pavement. The spend a lot of time flying at Baldwin. I have seen an Avanti edf fly off of our field. After seeing videos of the flex jet flying off the grass I decided to buy one. I am going to try again this evening. If it doesn't get off the ground it will go up for sale and i will look at the Avanti. I have the flex extra 300 which i really like.
Sep 18, 2019, 11:18 AM
Registered User
Quote:
Originally Posted by rocket_33
Had a similar thing initially. Two things, first are you taking off of a grass runway, geotex, pavement? Second, CG is critical I find with jets and EDF. Did you verify the CG position? Nose heavy makes it tough to initiate the rotation

If you are taking off of grass and CG is correct, keep light up elevator pressure on the roll to help unload the nose wheel and allow speed to come up and ease more up elevator in to lift off. Again if your plane is nose heavy you need t correct that first
I am flying off of grass. I checked and i have the cg spot on. I did that with the elevator and even with applying the high rate elevator at max when it was obviously at full ground speed it would not rotate.
Sep 18, 2019, 11:51 AM
Registered User
Is the elevator moving in the correct direction? Not being smart at all. I have seen it happen before.
Sep 18, 2019, 12:02 PM
Registered User
Quote:
Originally Posted by Mtnflyby
Is the elevator moving in the correct direction? Not being smart at all. I have seen it happen before.
Yes, it is moving in the right direction.
Sep 18, 2019, 01:47 PM
Registered User
Quote:
Originally Posted by foundryratjim
I am flying off of grass. I checked and i have the cg spot on. I did that with the elevator and even with applying the high rate elevator at max when it was obviously at full ground speed it would not rotate.
You and I have probably run across each other then as I have started going to Baldwin as well.

The FlexJet will take off from grass (takes a longer take off roll) but it does. Of course if your grass is above the height of the wheels, then the odds become less. I flew mine off of grass and, if you look way back, you can see where I asked the same question you are asking and the answers I am providing you are the answers that helped me resolve my issues.

Wish I were closer to you so could go over your setup. I can tell you though using high rate elevator will actually make the ability to lift off less as if you pour it all in, you create alot of drag. You cannot horse it off the ground like a prop plane.

May I ask, is this your first EDF? Not being rude but it may help explain some of the issues.

Where EXACTLY is your CG at and how are you checking it?
Sep 18, 2019, 01:56 PM
Registered User
Quote:
Originally Posted by foundryratjim
I am flying off of grass. I checked and i have the cg spot on. I did that with the elevator and even with applying the high rate elevator at max when it was obviously at full ground speed it would not rotate.
Not to doubt you on the CG but I just looked at my setup. You said you are running a Roaring Top 5500 pack. I am running a Pulse 5000 pack. Looking on the web, your pack weighs appx 825 grams as opposed to mine at 765 (60 grams different). Also my back is rearward as far as it goes so it makes me thing that given a heavier pack, you are nose heavy which could be a part of the problem.

The height of the grass could be another issue
Sep 18, 2019, 02:08 PM
I Used To Have More Free Time!
Are you sure there was not a tail wind?
Sep 18, 2019, 03:54 PM
Registered User
balanced it where the manual stated. This is my second edf of this size. I have a motion a10 also. Our field gets mowed again this friday morning. I am going to try it again that afternoon or evening weather permitting. I am also going to move my cg to the rear a bit.
Sep 18, 2019, 03:54 PM
Registered User
Quote:
Originally Posted by NCRealEstateGuy
Are you sure there was not a tail wind?
There wasn't any wind.
Sep 18, 2019, 04:47 PM
Registered User
Go4it's Avatar
Quote:
Originally Posted by foundryratjim
There wasn't any wind.


Flick shows the flexjet hovering. So You should have the power to take off the grass unless it's a foot tall.

FlexJet TV - Quique One Take (2 min 47 sec)
Sep 18, 2019, 05:04 PM
I Used To Have More Free Time!
That is the TV version. 8 cell.
Sep 18, 2019, 06:10 PM
Registered User
Quote:
Originally Posted by rocket_33
Not to doubt you on the CG but I just looked at my setup. You said you are running a Roaring Top 5500 pack. I am running a Pulse 5000 pack. Looking on the web, your pack weighs appx 825 grams as opposed to mine at 765 (60 grams different). Also my back is rearward as far as it goes so it makes me thing that given a heavier pack, you are nose heavy which could be a part of the problem.

The height of the grass could be another issue
Here is my balance point location


Quick Reply
Message:

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Potenza Aura 8 AFCS - Flex Innovations - Official Thread dribbe Radios 3463 Oct 12, 2019 08:20 PM
Discussion JETI and Flex Innovations Aura 8 AFCS compatibility? MarkDill Jeti USA 235 Feb 04, 2019 09:44 AM
Article Flex Innovations Cessna 170 High Wind Flight at SEFF Jason Cole Scale ARF/RTF 3 Aug 28, 2017 10:25 PM
News The Mamba Has Arrived - Flex Innovations! Jim T. Graham 3D Flying 9 Nov 03, 2016 03:18 PM
Article Flex Innovations - A New Warehouse and Website! Jim T. Graham Electric Plane Talk 15 Feb 27, 2016 09:38 AM