Lear 55?

[Kingairrick]

My pricipals are looking at a lear 55. Any info would be appreciated.

I keep hearing that they are underpowered. Conklin and Dedecker info doesn't show a huge difference in climb/speed vs. the 60...

Why the bad rep?

 

[doubtful]

ahhh, the mighty 55

I only have about 500 hours in the 55 but can probably get you started...
Power - with only an extra 200# of thrust per side over the 35 the plane is a runway hog, at times. Like most planes as the temp get to the mid 20's and above (C) your ability to take as much fuel as you would probably like diminishes unless you have a decent runway to work with. I can send you a Simuflite book that has the tab data in and you can look at what your typical profile comes out to be with it.
Weight - on the two that I flew the bow was about 13,500. Max zero fuel is 15,000 so if you are filling all the seats and they have plenty of bags that can be an issue.

I have never flown the 60 but the guys I have talked to have all indicated that it is a much better climber, going straight to 410 whereas the 55 can't. I have heard however that to the pax there is little difference. The cabin on the 60 might be a bit bigger but that is about it. The pilots like the 60 better cause of the panel, and also you can get a real lav that is serviced from the outside.

Just some quick thoughts off the top of my head. If you need more info let me know...

 

[Jump Pilot]

80 degrees
21,000 lb
Flaps 8
1,000 ft elevation

field length 6840
138, 143, 147

Comfy cockpit compared to the 35.

I think there was a post a few month ago regarding the 55.

 

[LJDRVR]

The 55 is a great airplane for the money. I just spent 3 hours in one today tooling around Texas. It is a dog compared to the rest of the Lear fleet. There is no comparision on the 60. A 60 will outrun ATC's computer that displays your altiude on the controller's data block. Rocket ship.

The 55 is plenty fast in cruise it just takes a bit longer to get up there. The biggest limiting factor is what type of missions/loads you intend to fly. As previously stated, the 55 is a runway hog. If you plan to routinely frequent rural strips, and then depart and fly halfway across the country, then it's not your plane. If you are planning on routinely visiting ASE, TEX, EGE, GUC, then forget it, unless your owners don't mind stopping immediately for fuel.

For instance, ASE on an 80 degree day at 16K and 4 pax=2500 pounds of fuel max. (Just gets you to Pueblo)

Or;

Long trip with a full airplane (Fuel & PAX) from sea level on a 100 degree day: 7810' field length. O.K for a nice big airport, but it does limit the utility of the jet.

The 55 is nice to fly and PAX like it. (First jet I took across the pond.) Lot of airplane for the money. PM ime if you need any help.

Good Luck!

 

[Corporate Dream]

what are typical cruise speeds for a 55?

 

[doubtful]

cruise speed

0.77 Mi about 440 KTAS
on some of the planes if you hit the .78 mark the rumble off the wingtips becomes very annoying

 

[Corporate Dream]

that's slower than I expected. How about the faster Lear's?

 

[LJDRVR]

.77? Nah, on a 55 with newer engines and a straight airframe, you'll have to pull back during cruise to keep from going through .81 (MMO) One of our 55's will do .80 all day long.

There is a fair amount of false perception out there that Learjets fly faster than anybody. Not true. Even the 35's redline at .83, which you'll never see in cruise anyway. What they are good at is climbing quickly. The 31 will go from sea level to 410 in 16 minutes with a pretty good load. There are lots of other business jets that will perform well in this area, but the Lear was first. I don't have any 24 time, but I've heard they'll climb 3000+ FPM out of FL350.

Delightful airplanes to fly.

 

[SenorSpielbergo]

Yes, LJ-24/23 (with healthy engines) has astounding climb performance. I concur with you on your statement about LJ-55 cruise performance as well.

"on some of the planes if you hit the .78 mark the rumble off the wingtips becomes very annoying"

Could that be extended spoilers?

 

[Corporate Dream]

Thanks for all of the info.