Recently downloaded the ERJ-170 Mega Package for FSX from Luis Quintero that was listed in Simviation.

I love the aircraft, but am having a stability issue.

The aircraft will not cruise stable above .70M & FL250 without porpoising. That shouldn't be outside the a/c's envelope.

I realize that setting trim may help, and have tried different settings, but nothing has worked, and there is nothing on the FMC to reference a trim setting.

Also, tried emailing the author of the package, but haven't heard back yet.

Any help would be appreciated.    Thanx.

I don't have this airplane, but sometimes the behavior you describe is due to improper weight and balance.  Please ignore if you have already taken W&B into consideration.  

Downloading now and will do a test flight to see if I concur with your situation.

UPDATE:  Smooth as butter at flt250 and MACH .70 I took off from my test airport, did a 90degree turn and set the AP for 25,000 and engaged AT for proper speed. I took off with 50% fuel in all tanks.  I really hope you are not using 100% fuel load.

Are you also turning on the "Probes", probie?  CRJ-700 speak for Pitot Tube heat.

It ain't the aircraft that has a problem!😉

 

 

I love how hands-on you are Charlie.  🙂

11 hours ago, BF Bullpup said:

I love how hands-on you are Charlie.  🙂

How better to answer questions about aircraft?  As long as I don't have to pay to download and try something, I'm up for it!😉

I read the response by Charliearon.

I have over way 1000 hrs in FSX & over 1500 hrs in Falcon 4. I am not a newbie. I have not had this issue in any other a/c in FSX including the E135/145 or 190, so I do know what I'm doing (despite what may have been implied).

I tried another flight last nite. Here are the flight parameters for the E-170 House Colors (however, I have the same problem with other a/c that were included in the same E-170 pkg).

Fuel (10,442 LBS/50% wings & center tank), Load (13,943 LBS ), Probes & Anti-ice (ON), AP/AT (ON),

NAV/GPS (ON), 265 KIAS / FL300, FD (ON), Yaw Damper (ON), Alt Hold (ON), Flaps (UP),

Spd Brakes (OFF), default trim before flight showed (2) lines forward of middle & within Red Zone balance. All nothing unusual. A/c porpoises w/ 500' up & down oscillations.

Am also curious as to why I only need 50% fuel as mentioned by Charliearon.

So someone please explain what is wrong.

Thanx.

As far as for testing purposes, I never use full tanks.  How far was your flight?  Did the distance require full tanks?  Did you do appropriate step-climbs to your altitude?  

I am re downloading the package and will retry the test flight at higher altitudes above flt300.

I just did another test flight from LO8 setting the A/P for 090 degrees and first altitude step of 12,000 feet.  100% full fuel load.  Speed set for 255knots IAS.  The first step was at 1800fpm.  After about 5 minutes, the second step to flt190 was at 1600fpm.  After about 5 minutes, third step to flt280 was at 1000fpm and then speed was set to finish the climb to flt360 at MACH and 800fpm.

I reached flt360 and had a 90knot tailwind and carefully set speed to MACH.70.  I had slight porpoise of less than 100 in each direction.  I have no ideas about how to keep it from doing that at these cruise altitudes.  Maybe "borrowing" .air files from other aircraft??

 

Only thing I can think of at this point is that maybe I have some corrupted files. Since I haven't had this problem with other a/c, I didn't think that would be the problem. Will have to try that I gess & see what happens.

Thanx for the other advice.