| Author | Message | ||
     michal Unregistered guest |
what is the Express' optimum cruising altitude to achieve: 1. maximum TAS 2. best specific range (nm/per lb of fuel). thanks. | ||
| wayne Unregistered guest |
you can't have both ,even with the EX2K. With a NA engine, max speed is where you make the most power and that is as low as you can get. Best range is at a lean econ setting. I would suggest that you climb to the point where at full throttle you are at 23"mp and stop there. You still get about 68% power. Or you can use my approuch. I have already spent xxx$ on the plane ,I want to get there as fast as I can, so unless you need to conserve fuel(to cover poor planning and at that point it's to late to lean back) run the girl like she's rented! what's another 2-3 $ an hr. on top of hanger rent(not me),insurance... | ||
| michal Unregistered guest |
you can't have both I never said I expected both at the same altitude. Therefore I was hoping for 2 answers. that you climb to the point where ... OK, so how high it is for Express, just a ballpark ?. I don't have the aircaft so it is hard for me to start climbing to find out ... thanks anyway, maybe someone will know... | ||
| Jeff Dingbaum New member Username: Aviators Post Number: 19 Registered: 12-2000 |
What type of engine are you going to put in it? Isn't that what really determines how high our birds go? The Deltahawk diesel makes 100% power at 17,000 and over 60% at 30,000. Of course, the Express isn't pressurized, so you need to worry about oxygen, but if you are going to use a turbocharged engine it will be higher. | ||
| michal Unregistered guest |
Thanks Jeff. I am thinking, standard, recommended, Continental IO-550-N 310 hp. I don't think it is turbocharged but I may be wrong. Yes, pressurization would be then be my next question. If the optimum altitude is above say 12,000 ft is it possible to have an installed oxygen system like some aircraft do or basically I have to use a portable one. | ||
| Tom R. Hutchison New member Username: Tomhutch Post Number: 152 Registered: 01-2003 |
Since you are building an experimental aircraft you can design in an oxygen system as elaborate you wish to undertake (taking W&B into account of course). Or a portable sytem if you don't want the complexity and building time of a built-in system. Tom | ||
| wayne Unregistered guest |
Before you build in the extra weight of an O2 system and install that super/turbo charger, you should take a REAL look at you mission profile. Are you really going to climb to 14000+ feet and stay there for 4-5 hrs? If so you must be flying easterly(downwind) most of the time.otherwise I will beat you there down low,cause you wasted time climbing and hauling all that extra support equipment( turbo,oxygen,speedbreaks and dealing with ATC as you are on IFR flt plan)the gas you "saved" will be spent on turbo overhaul. To each their own but the more one is secure with themselves the more $$one saves not having all those "big pilot watch" items FYI, I just took up our plane for it's 2nd birthday (270hrTT), at 2000'PA, 26 degrees, 28.7"MP/2700rpm,27GPH I was going 183ktTAS. Checked 2 ways on the GPS. That is way to much gas to burn to go over 200mph even for me. To answer the guy's ?? you get max range by flying at the best L/D AoA and that doesn't change with altitude. And SL is where you make the most power to go the fastest. So at sealevel you can have both, but at different speeds. Now get busy your planes!! | ||
| Roy Davis New member Username: Royhdavis Post Number: 43 Registered: 01-2003 |
We are waiting with baited breath the results of flying the IOF-550N, the FADEC version of the Continental engine. The magneto engines don't have spark advance, which robs power at altitude. Won't be as good a turbocharging, but better then NA and mags. Hope to start popping out the IOF-550N equipped aircraft in August. | ||
| CBROS Unregistered guest |
Michal: If you will send me your E-mail address I will send you the results of some recent fuel burn tests we ran on our IO-540, CT Express. Send to:bnent@pacbell.net | ||
| michal Unregistered guest |
CBROS: My email to you is bouncing back (tried twice) - unknown address. Maybe you could try mine: michaljast@sbcglobal.net Thanks. |