Anyone happen to have a performance profile set up in FLTPLN dot com for a CE501 Eagle II?

I don't but when I test flew one, I was disappointed with its performance. The fuel hump added to the wing causes drag to increase quite a bit above mach 0.6 and that limited cruise speed as compared to a Stallion (Williams engines but no fuel hump). At FL410, I think we were unable to get it above mach 0.63, ~360 KTAS.

The extra fuel does extend range, but is goes slower and in a strong headwind, the range is not that much more than the Stallion. The real test of range is bucking a strong headwind. I have not flown the Stallion, but I think it goes 390 KTAS pretty reliably.

My conclusion to this is that I would rather have the Stallion if I wanted a 501 with Williams. Significantly faster than the Eagle II.

This was all from flying one example, but my aerodynamic friends confirmed the high loft of the fuel hump would cause drag issues as mach number increased, so I think it is reasonable to extrapolate this to others.

This advice is worth what you paid for it.

I ended up buying a Citation V instead and avoiding the Williams ecosystem. Program prices for the FJ44 are now $400/hour for a pair.

Mike C.

One word, CAPEX. Find me a V with a similar panel, similar P&I, and similar times, at the same price, and yep, I'm all in!

It will go 1600nm Westbound usually with decent VFR Reserves. 375kts with the Hump.

Williams just came out with an HT Disk AD...no bueno.

I question the 375 KTAS based on what I saw, 360 KTAS was all we could get at FL410 and we were well below gross. It won't do 375 KTAS *and* go 1600 nm, I suspect.

The Stallion does 1500 nm and 390 KTAS, as reported by others though I have not verified this personally. It isn't a lot less range because it goes faster and climbs faster with less weight, so it gets to altitude quicker with lower fuel flows.

There is a small zone where the Eagle II does it non stop and the Stallion has a fuel stop. Even in this case, the extra speed of the Stallion makes up for much of the fuel stop time.

Part of my preference for the Stallion was I had seen an example Eagle II where the workmanship on the fuel hump was shoddy and it had leaks that looked potentially chronic and unfixable. I think I would prefer not mutilating the wing so much.


For engines off program, this is a problem. I wonder how Williams will punish those off program who need this work done since I suspect Williams is the only shop that can do it. I could see cases where Williams opens the engine and decides you need a lot more work than you asked them to do. It could get ugly.

On program, I would expect it to be covered since the AD is basically forcing an existing SB. For Williams, they make it basically impossible to be off program.

Mike C.

I just had this AD performed earlier this year. Off program the parts were quoted as about $205,000.00, for both engines. You have to fly two mechanics in from Williams to perform the work which took about 3 days. On program the cost was zero. This, besides Premiers, AD also affects some CJ 2 and some CJ 3. For some reason it is only a few of the planes in this model group. I do not know how many of the modified planes it affects. If they use this engine it probably does.
I am glad I am on the program. Williams was great to work with.

This is exactly why my original request was asking for FLTPLN . com profiles. I've found the 501 profile in FLTPLN to be very accurate. If I can get a a profile for an Eagle II and a Stallion, we can really compare performance.

Personally I don't think a Stallion comes even close to an Eagle II in range. But ... see comment above. I'd like to see some real profiles.

I thought the same, but my test flight revealed some issues especially at higher altitudes and mach numbers. Maybe my test airplane had some defect or issue that limited its performance.

It is going to be hard to get a high fidelity fltplan.com profile unless someone has put in the time to tune it. I didn't immediately see a profile for either the Eagle II or Stallion.

Your question is perhaps better asked on the Citation Jet Pilot (CJP) website. You are likely to find more operators there, but it does cost you $500/year to join. I know one active member has a Stallion he has flown for years. There is probably someone with an Eagle II as well.

Mike C.

501 SP a GREAT PLANE!

Agree. Turns out a request was made by another member just a month or so ago on CJP. I just bumped it back up to the top of the list.

Just doing some farmer math -

We know the Eagle II holds 4500 lbs of fuel vs 3800 lbs in the Stallion (18.4%), has the same engines, and goes slower. How much slower? Looks like between 2% slower and 8% slower. Let's say 7%. That would say the Eagle II range should be about 10% more than the Stallion. That seems to pass the laugh test.

What's puzzling is the Sierra numbers in their old brochure. 2% slower and 25% better range?

Some considerations:

The Eagle II has a higher empty weight and carries 700 lbs more fuel so it climbs less well and cruises slower just from extra weight.

I was always testing range in headwinds since being able to do round trips non stop is the goal. A plane that is slower will be more affected by headwinds.

When you want max range, you need to fly high. At FL410/430, the Stallion does about 390 KTAS and the Eagle II does about 360 KTAS from observation and reports from owners. The max speed numbers occur at altitudes not where the max range numbers occur, as one might expect.


I wouldn't trust Sierra's brochure numbers all that much, but the way this can occur is that you have to delete reserve fuel from the calculation. Say you set that to 800 lbs, then the Eagle II has 3700 lbs and the Stallion has 3000 lbs for a trip, an increase of 23% in fuel. Useful range is not to empty tanks.

But even so, at the extra weight, longer climb, slower cruise, I don't believe the Eagle II range is 25% more than the Stallion. My assessment is that in a headwind it was maybe 10% more. That wasn't enough advantage on enough days to make up for the disadvantages, IMO. Basically, the increased range is a lot less than one expects from the specs when subjected to real world situations.

Again, much of my assessment is based on limited data (though one actual Eagle II test flight), so your results may vary.

Mike C.