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How long does FWF take?

TCONROY

TCONROY

Well Known Member
We are getting really close to placing the order for our IO-360-M1B and Hartzell BA prop from Van's. I've never worked on an aircraft FWF so it will all be new to me.
I'm trying to gauge how long it will take to get the FWF complete (hang engine, mount accessories, fittings, hoses, cowling, spinner, baffling..etc). I know it completely depends on how many hours a day are spent but for the average builder working 40-50 hours per month how long can we expect it to take?
 
It somewhat depends what other accessories/sensors and modifications the builder is going to do, but I suspect if you are going to follow VANs suggested plan and equipment, it should not take more than 4-50 hours. Of course, it always take longer if you work 2 hours here and there as oppose to 8 hours a day sort of way.

Of course this would be only for FWF and not cowl/engine baffling, etc.
 
Engine hanging should only take 2-4 hours including setup to hang it.

Hooking up all the misc stuff like probes etc... A day to 2... Not 8 hour days either...just plugging away at each system.

Baffles! Now your talking fun! How can something so simple take so long? :mad: give that a weekend with you and Dad!

Cowling, depends on how things line up. But another Full weekend to get it matched up and ready for final fitting.

You going with all those fancy AFS touch screens? Or did you lose you discount :D
 
My Experience

I received my new engine on July 15 and will probably be flying this weekend. I work during my lunch break almost every day, a couple hours in the evening three days a week, and about 6-8 hours each weekend. When the engine arrived, my baffles were already done (I fabbed them when I had a different engine) so I just had to bolt them on. Also, my cowl was already fitted. I had not completed the filtered airbox previously (vertical induction fuel injection). So, like everybody else says, "it depends..."

I pulled my Subaru FWF off last October, and worked hard until about February (that's when I did the baffle fabrication and cowl fitting), but I also had to do a complete electrical system rework in that time. I twiddled my thumbs from February until my new engine arrived last month.

Good luck. It's all pretty straight forward!
 
It took me longer than ol' Smiling Jack! :) I have over 250 hrs into mine...but that includes everything...baffles/plenum, cowling work, wiring, GPS antenna mounting, etc. And I was, like you, learning as I went since it was my first time doing it.

Its going to depend on how simple your setup is too...mine is not what I would consider "plain ol' vanilla" since it included the SJ cowl/plenum and a Rod Bower ram air unit. I had to do surgery on my cowl to make all this fit. I also have a bigger oil cooler so making that fit took some extra time. Anything that you have to modify from stock is going to cost you in time. There are so many variations with FWF its hard to tell how yours will turn out.

The basics of the FWF (the engine stuff) is not very difficult though, it just depends what you consider FWF...is the cowl FWF? Maybe not...

Good luck...if it helps any, this was my favorite part of the build.
 
I hung my engine on the fuselage right after Christmas and I'm pretty much done with the FWF work as of August. I do some steady weeks of progress, and others get interrupted by work/travel.
Cowling can take quite a while to get it completely done and ready for paint. Baffles went smoothly, but it is definitely an iterative process. FAB took a little over a week (anything with fiberglass is slow process to get through depending on your level of quality you want to attain).
I'm sure the next plane will go much quicker because you have experience. I spent a lot of time just trying to figure out how to do FWF work, because Van's doesn't have a lot of instructions in the builder's manual.
Buying stuff takes time, so figure out what you need and try to have it all on hand before you start.
 
If you purchase the firewall forward kit for your engine it will speed things up dramatically. You wont have to research and order every part, hose length, etc. individually and, it comes with instructions.
 
I'm almost too embarrassed to post, I probably spent 10 hours running plug wires.....
Hanging engine only took a couple of hours, adding stuff to the firewall/removing engine mount and reinstalling took another 10 hours.
My engine was a little different (HO-360-a1F6D), I probably have 50 hours in ordering/routing hoses and fittings.
10 hours in engine sensors.
30 hours installing single electronic ignition, uninstalling single and reinstalling dual electronic ignition.
60 hours for baffling
25 hours on he FAB
Cowling took most of a winter 150 hours fitting/sanding/filling/sanding/primer
Firewall penetrations.....
I spent more time running through different scenarios, starter cable on left side under tubes, perhaps over tubes, what about on the right, right side it is now do I go under the engine mount or over etc.
if I ever build another airplane I will be 4 times faster.
All times are just a guess, I quit logging my time and receipts prior to completing the tail......I'm happier not knowing for sure.
 
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Like Ron said, SJ cowl takes longer.

He does bring up a great point that stuck out regarding the oil cooler.

If you are hanging it off the baffle (like I did) you need to beef that up!

Or...like me you will end up pulling it apart after the first 50 hours fixing a crack! Yup....add another 8 hours :mad:

There are plenty of posts here on what people have done.
 
All depends

Complex? First time? Don't count on zooming through it.

I could have written CrabAndy's post. Maybe all that time spent is what made Andy a Crab. :)
 
18 months from receipt of engine to first flight.

I ordered the engine at SnF expecting 8 to 10 week delivery but it darned near beat me home so I was not quite ready for it.
I was still doing penetrations and wiring.

Hung it 6 months later.

Remaining work was as follows:

Baffles
Cowl
FI Snorkel
All connection terminations
Wing incidence
Wing wiring
Rigging
Remainder of all fiberglass on whole plane.
Find method to move to hangar
Dissasemble
Move to hangar
Reassemble (wings were a b**ch)
Preflight testing and debugging (this took 2 months)
Paperwork
Rubber Stamp
Transition training
Creation of test plan
Collection of balls
First flight.
 
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mburch said:
For me? A couple years so far. But I'm a slow worker. :)

mcb
Click to expand...

Yeah, me too, I am slow. But, looking at Matts website, at least I don't measure time by three plants growing in a 5 gal bucket . . . . not yet anyway.

I got my SnF "special" engine from Van's just after 2012 OSH. I don't know what takes so long, but looking at Matt's and seeing the mill mod to the heater cuffs, there seem to be a lot of those for me too.

Although I am building full time (ROTFL) my friend said it will be a year to first flight. Maybe it was reverse psychology, cause it has made me focus better.

"They say I'm lazy, but it takes all my time. life's been good to me so far"
 
It took me three months. I worked almost every day, but not all day on it. Take your time. It will come together very quickly.
:)
Dave
 
Keep in mind I'm a s-l-o-w builder ...

SJ cowl & plenum - 260 hrs
all FWF work - 155 hrs

Engine sensors were tallied as part of my wiring tasks. All wiring work (i.e. wings, fuse, panel, engine sensors, etc) - 230 hrs
 
Thanks a bunch guys! Your comments give me a better feel for the work ahead. I think it is very reasonable to hope for a first flight in Spring '14. I have a pretty solid timeline I work with and I always seem to meet the goals/deadlines I set for myself.
At this point I still sleep a little better each night now that the tip-up canopy is done. There can't possibly be anything that is more work and as frustrating! :D cough baffles...cough cowling :eek:
 
18 months from receipt of engine to first flight.

I ordered the engine at SnF expecting 8 to 10 week delivery but it darned near beat me home so I was not quite ready for it.
I was still doing penetrations and wiring.

Hung it 6 months later.

Remaining work was as follows:

Baffles
Cowl
FI Snorkel
All connection terminations
Wing incidence
Wing wiring
Rigging
Remainder of all fiberglass on whole plane.
Find method to move to hangar
Dissasemble
Move to hangar
Reassemble (wings were a b**ch)
Preflight testing and debugging (this took 2 months)
Paperwork
Rubber Stamp
Transition training
Creation of test plan
Collection of balls
First flight.
Click to expand...
:eek: :eek: :eek: :eek:

Bill, I finally got moved into the new house and got the wings back in the jig.........I think I'm gonna sell this thing after your post! :D
 
Double It!

Reference the mountainer's mantra: 1) It's further away than it seems; 2) It's taller than it seems; 3) It'll take longer than it seems.

By the time I got to FWF on my -8A I became very aware that this work was serious regarding operation of the aircraft and I would have to live with the decisions I made. Therefore after developing an initial build plan, I spent a lot of time doing "What if's?" regarding component placement, workflow, etc - even basic architecture. You will not only be addressing the obvious - engine, cowl, baffles - you can be thinking about "a better way" for fuel system components, electrical components, control cables, GPS/XM antennas, brake system, sensors, wire runs, etc.

I found that completing some of the work - and actually seeing the results - opened the door for potential improvements in other areas. I spent a lot of time deciding rather than doing. Don't forget to ask, "If I do this to "A", what does that mean for "B, C, D------Z"?

In many cases I reverted to the original plan, but was glad I took my time and put some thought into what the optimum result might be.

340 flight hours so far with no design regrets.
 
Ball Collecting Ensues

To save time and to be ready when everything is done, I am starting ball collecting right now!
 
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