F6F Hellcat Build

[Swale]

So I've taken the plunge and gone with a YT Hellcat, after much research inc telephone calls to YT I'm satisified that the gear mounts on this model are somewhere near upto scratch (or atleast as good as can be reasonably expected given the price) I will most likely be taking andy B's advice and looking at ways to further re-inforce the mounting as there seems to be some working room according to the pics of the wing that I have seen.

The model will be of a simlar size to the BH FW190 prior and hopefully of much better quality.

I will start to gather bits a bobs to finish this model...so far I have the retracts from YT coming with the kit wednesday.

Now, one thing I'm debating about is its engine I have an eye for one of the Laser 200v or 160v (twin cylinder versions) where as normaly I would go with a saito im drawn to the twin cylinder as there price seems reasonable compared to other manufacturers.

But my question is what are the pros and cons of these twins vs single cylinder engines?

I here that pretty much vibration free but less powerful than there single cylider counterparts I also here that lasers are slightly lacking in power compared to other brands.

I was more leaning toward the 200v as Im guessing this will have enough power for a convincing scale flight with the ability to pull some aerobatics loops etc with out stalling/running out of steam at the top?

The model is pojected to weigh in at a whisker under 7kg with careful selection of batterys etc but Im also expecting it to be handicapped with lots of drag.

So whats your thoughts people.

p.s If I dont go laser Id probably end up going with a saito fa 180 or 220 zeus im goin of the policy that I may aswell have a bigger engine than lead weight up front.

Heres a pic.

[Swale]

Just had a quick chat with John at laser whom seemed very helpful indeed....he told me to pop down with the fuselage and cowling and he will throw together a 200v to dummy test fitting....

am looking at a 4 week wait from order but im in no rush and they sound although there worth the wait.

[simonh]

Very nice Looking forward to seeing this one. Have added as article to front page.

[Gareth]

Just had a quick chat with John at laser whom seemed very helpful indeed....

If that is John from Slough models he is a great guy.

Just as a note, if you take a look at the BMFA Hand book 2010 Page 43 "MODELS BETWEEN 7kg AND 20kg" specifically Point "H":

(h) It is recommended that all ‘large model' pilots
should hold the BMFA ‘B' certificate or its equivalent
(e.g. SAA Silver Wings, LMA Certificate of
Competence), and should ensure that both
adequate third party insurance is operational and
that all flights made comply with CAA regulations.

If you do go over the 7kg mark you will have to contact the CAA for each flight (Number can be found on the bottom of the flight board). Even if you are close i would check it regularly as if you get fuel leak or even if the wood takes up moisture from the air it will push it over the 7kg mark and you will then have to think about other things.

Plan for the model to be over 7kg and if its under then all the better.

Gareth

[andyb]

I think if you're going for one of those, it'll probably end up more than 7kg (particularly if you're going to a) strengthen the u/c and b) put in a larger engine) with all the hassles that entails on each flight, as discussed above.

Personally, I'd use a Laser for all the reasons previously discussed.

And - again speaking personally - I'd look getting a B test (or at the very least an A test) organised as soon as possible. I'm not suggesting that you might fail it, merely that in the heat and pressure of the moment, one's flying may degrade to the point where it is no longer felt to be of anacceptably high standard. That's what happened to me, anyway.

rgds

A.

[simonh]

Have split off the posts about flying models over 7Kg as it was getting off topic from Swale's build notes. Please post up in the split topic if you want to comment on flying models over 7Kg, thanks.

[Russ]

Great project Swale. Look forward to seeing it come together.

If it's not too much of a distraction could you blog us a build thread on the building board. Threads on that board are never archived or deleted as part of our admin clean up.

Just to echo what others have posted, Laser engines are fantastic and very reliable/non fussy!

Not sure what the size (span) of this model is, but we have had many club members over the years flying 6ft span YT warbirds very happily on Laser 150s.

[simonh]

Russ - thats a good Idea..... To save Swale from having to start a new thread, I'll just move this over to the building board.

[Mike71]

Look forward to seeing this. I think I've banged on about Laser engines enough in the past, suffice it to say they're very reliable. I'd love to see one of these on the go. My Spit is far from complete but i've got a Laser V in mind for my next project, hopefully a Jerry Bates Bearcat. It's a long way off but you've got to keep dreaming.

A word of warning. At the risk of repeating myself Laser carbs enter the engine at the top of the cylinder, but in line with normal setups the fuel tank still has to be in line with the needle. Most ARF's are setup with the tank position in line with the needle of a conventionally sited carb ie much closer to the centreline of the engine. For me mounting my engines inverted on my Extra and Eagle in order to fully cowl them, this meant dropping the tank about 10cms, not an easy job involving much butchery in a fiddly place. Of course I could have made it easy for myself by side mounting them, but I wanted them fully cowled. That said you could probably mount your 200 V upright in the large Hellcat cowl, and the V configuration means that the carbs are much closer to the centreline than on my single cylinder jobs.

Lasers are pretty heavy, which you'll probably need to get the c of g in the right place in that stubby nose.

cheers

[Swale]

So the hellcat arrived today I managed to get a little peak at the bits and bobs....Im thus far very impressed the finish looks great the quality appear to be top notch havent had a proper look at the landing gear mounts as it is covered over, but managed to peak down the end of the wing and the wood looks of a good quality thick and strong Im more than prepared to do re-inforcements if necessary.

Heres a couple of pics.....

Gordon seemed thrilled with the idea of coming over to the allied side and couldn't help but try out the new cockpit for size......





Unfortunatley Gordon is somewhat scarred by his ordeal with week retracts and was very keen to check out the YT offering....thankfully he was pleased!!!


somewhat begging for a retractable tailwheel.....something to consider I think.

[simonh]

Gordon seemed thrilled with the idea of coming over to the allied side and couldn't help but try out the new cockpit for size......
unfortunatley Gordon is somewhat scarred by his ordeal with week retracts and was very keen to check out the YT offering....thankfully he was pleased!!!

Nice to see the old boy is still with us! Glad you have given him some good quality retracts. If something breaks in landing the poor old codger's ticker is likely to finally give out!

[Swale]

Well he is knocking on for 92 he just cant hack the bumps like he used to he needs oleos

[Swale]

So a little update, not much has happened but I have managed to build the wing flaps look very nice and large so hopefully should come in nice and slow...will be moving on to the retracts next.

[Russ]

Any decision on the engine yet?

[Swale]

Hi, Ah yes forgot to mention that I'm gonna go with the laser 200v won't have it for a few weeks as theres a bit of a delay on these engines at the moment.

Think this engine looks sweet hope it runs and sounds as good as it looks