Re: Baggage pods - test flying


Keith Spreuer
 

Many claim they add roll stability by straightening the air flow. Possible but I'm skeptical 


On Sat, Dec 7, 2019, 3:47 PM Marc J. Zeitlin <marc.j.zeitlin@...> wrote:
Dave Berenhotlz wrote:

... can any user of baggage pods give me a heads up on what changes they noticed with and without them in flight? Perhaps also full (heavy) vs empty.

As you would expect, the pods add weight and drag, as well as some roll inertia. Not a lot of weight by themselves, and not a lot of weight even when loaded with the 25 lb. allowable in each. So maybe 75 lb. total, located about on the CG. You won't notice much of an effect from the weight.

But they certainly add drag. The EZ's and COZY's I've flown with and without pods seem to be about 7 KTAS slower at altitude (+/- 3 KTAS) with the pods on them, and climb a few hundred fpm slower than without pods. YMMV a bit.

If you can notice a roll response difference with the pods vs. without them, then you're a better test pilot than I am (not saying much, of course - I'm not a test pilot). While they are outboard of the strakes, so outboard of the fuel tanks, they only hold 25 lb (plus their own weight), so they're the equivalent of maybe 6 gallons of gas. Not a lot of extra inertia, but some.

There are a couple of folks that have claimed that the pods made them go faster by a few kts. This, of course, is complete nonsense, and speaks to a lack of accurate data gathering ability. There's no way that adding drag to a plane makes it faster, obviously. There were some interesting theories as to why their planes went faster with the pods :-).

--
Marc J. Zeitlin                      marc_zeitlin@...
                                            http://www.cozybuilders.org/
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