Official Freewing JAS 39 Gripen 80mm EDF Jet

[janmb]

Great idea! Yes, planning to put a hobby eagle A3 Super in this as well so I think that’s what I’ll do. Thanks.

Most welcome :)

[janmb]

Just send me the plane now!😛

Tivoli canards and vertical stab be gone? 😂

[Anders Boström]

Tivoli canards and vertical stab be gone? 😂

yes, not because they're ugly, but it's not my cup of tea.😀

[xviper]

it would be really nice if those of us who pre-ordered the Gripen could also pre-order the TV so we could install it during the initial assembly.

I'm the same. May as well go full gusto and get the TV packed inside the same box as the plane. I'd rather not glue the stock tail on and then carve it up to swap rear ends. Is it possible to even pre-order the Gripen and the TV end at the same time? If not, I'll wait for the TV piece to be available before ordering the plane. It's going to be a winter project anyway.

[janmb]

I'm the same. May as well go full gusto and get the TV packed inside the same box as the plane. I'd rather not glue the stock tail on and then carve it up to swap rear ends. Is it possible to even pre-order the Gripen and the TV end at the same time? If not, I'll wait for the TV piece to be available before ordering the plane. It's going to be a winter project anyway.

Same here.

I'm going turbine in my Gripen, and seriously considering going for the first ever (as far as I know) foamie turbine conversion to feature VT lol

[xviper]

Same here.

I'm going turbine in my Gripen, and seriously considering going for the first ever (as far as I know) foamie turbine conversion to feature VT lol

I've never stood behind a turbine when it's running. Is the exhaust really hot? If so, do you think the heat would be an issue going through a VT nozzle that bends the flow?

[Airguardian]

Depends on how far away from it you are standing...

[Evan D]

We used to stand behind the F-4's to keep warm while doing carrier ops off N. Korea in winter. Didn't have to get very close!

[fredmdbud]

I've never stood behind a turbine when it's running. Is the exhaust really hot? If so, do you think the heat would be an issue going through a VT nozzle that bends the flow?

I assume you are talking about a RC turbine? Depends on the throttle setting - I've seen people walk behind a jet at idle power and during taxi. Spinning up and full power is a different story.

[xviper]

I assume you are talking about a RC turbine? Depends on the throttle setting - I've seen people walk behind a jet at idle power and during taxi. Spinning up and full power is a different story.

Yes, the RC variety. I'm thinking that the heat from the motor could melt the foam in the VT nozzle, especially when it's bending the flow.

[fredmdbud]

Yes, the RC variety. I'm thinking that the heat from the motor could melt the foam in the VT nozzle, especially when it's bending the flow.

The scorch marks on the blast deflectors at my field tell me the exhaust can get pretty hot! The turbine thrust-vectoring nozzles I've seen are of the metal-can variety. As long as there is insulation or an air gap for the foam, and the shielded nozzle retains some overlap with the thrust tube, that might work.

[janmb]

I've never stood behind a turbine when it's running. Is the exhaust really hot? If so, do you think the heat would be an issue going through a VT nozzle that bends the flow?

Nominal exhaust is typically in the high 500 to low 700 degrees C

I didn't say I was going to let the foam direct the flow, now did I? :D

Just like in the main body, there will need to be spacers and a metal thrust tube - in this case slightly larger diameter than the fixed version, to ensure thrust being pushed through it and not spill past it.

[jkallend]

Duplicate post - ignore.

[NorthernFlyer]

Those that have flown this plane: Can anyone tell me what time you are getting on the 4000 mah and 5000 mah batteries respectively; without vectoring installed? I trying to decide which batteries to pick up for it.

[crxmanpat]

Nobody has the plane yet except James from Motion, and a few guys in Taiwan (I don't think they're on this forum). They should start shipping out later this month.

[NorthernFlyer]

Nobody has the plane yet except James from Motion, and a few guys in Taiwan (I don't think they're on this forum). They should start shipping out later this month.

And Justin, and most likely Alpha. Was hoping one of them would chime in. I heard James mention that he was mostly flying on 4000s and wanted to know what kind of times he was getting.

[janmb]

And Justin, and most likely Alpha. Was hoping one of them would chime in. I heard James mention that he was mostly flying on 4000s and wanted to know what kind of times he was getting.

It is extremely hard to take anything away from the flight times overs claim. Not because they are not valid as such, but because even tiny differences in setup, conditions, temperature, elevation, and pilot flight style can make HUGE differences in the times you achieve on exactly the same battery.

For example, but Avanti usually has between 3:30 and 4:30 useful throttle time, mixed flight. My personal best was set just the other day, doing 9:57 airborne time, landing with 3.77 on the cells. The point being: Huuuuuge span depending on how you fly and what conditions apply.

[crxmanpat]

And Justin, and most likely Alpha. Was hoping one of them would chime in. I heard James mention that he was mostly flying on 4000s and wanted to know what kind of times he was getting.

Justin doesn't actually have one, he just went to visit James and flew that one. Maybe James can chime in.

[NorthernFlyer]

It is extremely hard to take anything away from the flight times overs claim. Not because they are not valid as such, but because even tiny differences in setup, conditions, temperature, elevation, and pilot flight style can make HUGE differences in the times you achieve on exactly the same battery.

For example, but Avanti usually has between 3:30 and 4:30 useful throttle time, mixed flight. My personal best was set just the other day, doing 9:57 airborne time, landing with 3.77 on the cells. The point being: Huuuuuge span depending on how you fly and what conditions apply.

I am also aware of this, but I am looking for a ballpark figure. Thank you, though

[janmb]

I am also aware of this, but I am looking for a ballpark figure. Thank you, though

Doesn't the set of videos we have seen this far provide some idea?

I used to love going large batteries in every model I had, but have realized more and more that increased capacity gives very little real increase in flight time. More weight makes the model less efficient and spends that energy faster. What it does do though is make the model heavier and at least in some respects fly worse.