Go Faster Kits

[IFollowRoads]

Just having returned from a wander about Europe, and with a CofA due next week, anybody got any experience of any of the 'go faster' goodies advertised, particularly in relation to an elderly Piper Arrow (180)?

I was considering the 'Knots2U' options, as they appear to be a more complete option than the LoPresti, but will take any advice or experiences into account, and it looks like I have to get it going before the end of the month with the impending change to the CAA's 'Mod' process.

TIA

[M14P]

Most of these mods seem to be relatively useless - think about it logically, there is very little you can do to change the basic aerodynamics of the aircraft.

I guess cowlings could make a big difference but rigging, nice paint and a good engine will be better places to concentrate.

Gap seals can give a slight speed advantage but can stiffen ailerons. On the PA24/30/39 the mods that do the most are the wing root and flap fairings since that area is quite untidy drag wise - BUT - the difference is all found in behaviour in the flare. Landing manners are greatly improved. There are virtually no speed gains.

As far as paperwork - if you need to raise a new page in the flight manual it'll be a major mod. The best way to approach any mod is to consult with the CAA beforehand(they really are quite 'real world') and produce a well thought out assessment of the work you intend to do. Even better, if it has an STC in the US then include that paperwork too.

[IFollowRoads]

I am willing to listen to the arguments both ways, hence the original post, but if there is something to be gained it strikes me as worthwhile to investigate.

On the principle that the a/c needs a re-paint anyway, if there are any airframe mods to be done, I would like to get them done first, and then if the speed gains can be made, there is a cost saving involved on the running costs in addition to the ability to get somewhere quicker. The "good engine" is going to wait until the existing one reaches TBO (or maybe with a little extension) as that's a particularly expensive mod to make. The rigging will have to be passed to the maintainer, but as he has owned his own Arrows in the past, and currently runs a PA28-180, will trust that he knows how to get this right.

The sellers arguments goes along the lines of "the original was built to a manufacturing price and has thus not been cleaned up" and "it wasn't thought out as well as it could have been in the first place"

I've already spoken with Major Projects at the CAA (and very helpful they were too), and as the stuff I'm looking at is all STC'd, hopefully this will make the whole process easier. Nevertheless, including new paint and windows, the whole job is looking around 6k sterling, so I'd like to make sure I get it right- preferably the first time!

Thanks for your comments and thoughts

[ 12 July 2001: Message edited by: IFollowRoads ]

[M14P]

Don't get me wrong - some of the mods are really cool (especially to look at).

The people who could tell you more would be the owners group around your aircraft - I guess they'll be in the USA.

Since you will gain probably only 5-8 kts total out of the mods it is best to go for the handling mods or soundproofing. You will still spend a similar amount of time in the aircraft so you might as well look into soundproofing issues in the form of new windows and materials within the upholstery. If it sounds too good to be true it probably is.

We completely revamped the cockpit - lots of money but it updated the aircraft to almost brand new condition.

Good luck with your project.

[LowNSlow]

Ain't no substitute for cubes. Cubic inches that is. If the budget stretches to it stick a 235 hp Lyc in the front. A snip at £12k plus the Major mod, plus the engine mount plus the new prop. It'll go 10-15kt faster, mostly due to your wallet being lighter!

I know it sounds silly but if you want more speed your better off buying an aeroplane that was designed to go faster. Try a Commanche or a Robin.

[A7E Driver]

I installed flap, aileron and stabilator seals from knots2u a few years ago. (I have an Arrow IV T-Tail.) In all honesty, I did not notice a material improvement in climb out or cruising speed. But, theoretically, I must be going a couple of knots faster.
:-) I did find that it was slightly easier to land --- but that may have been due to pilot technique as I got used to a new airplane. BTW, it was 19.5 hours of shop labour to install.