Q400 not reaching assigned altitude

Exelta

Hello all,

I've been flying the Dash for quite a while now, and yesterday it started to act strangely. I input the desired cruise altitude, press ALT SEL, and the aircraft will climb close to it and maintain that altitude, a few hundred feet below the assigned altitude (see picture by clicking on link below). It did it again today. I input FL250, and it levels off at about 24 880 ft. Had to manually set VS 200 ft/min until it reaches assigned altitude, then it maintains it. What am I doing wrong?

Thank you for your insights and suggestions, and congratulations for an amazing product.

https://docs.google.com/presentation/d/1sShzD1Kb9FBXgsUba2RszrZNYvIQcVzFUKDrd0RcCmw/edit?usp=sharing

É.

aua668

Hi,

Which climb mode did you select? Pitch Hold, VS, IAS? Only pressing ALT SEL does nothing but leveling off if you reach the selected altitude.

Rgds
Reinhard

Exelta

IAS all the way up to FL240. I've been flying the thing for months (years on and off), it's a new thing for me that it does not reach the selected altitude. On my picture you can see it did not reach the selected altitude. I'll try again today.

Exelta

Tried again, no problem this time... Could it be that I asked for a 210 IAS climb instead of 200 IAS, which I usually do, and it could not keep this speed until FL250 and just stopped climbing a few hundred feet before ALT SEL?

jpgmultimodal

Hi,

One method is for Type I (High Speed Climb) as follows:
The standard climb profile is IAS 210 to FL150 and 5° PITCH thereafter.

All the climbs:

Type I KIAS210 Up To FL150
KIAS200 At FL170
KIAS190 At FL190
KIAS180 AT FL210
KIAS170 AT FL230
KIAS160 AT FL250

Type II KIAS185 Up To FL200
KIAS180 AT FL210
KIAS170 AT FL230
KIAS160 AT FL250

Type III KIAS 160 Up To FL250

Regards,

JP

aua668

Hi,

The three types of climb are often referenced by the following names:

• Type I (high speed)
• Type II (intermediate speed)
• Type III (low speed)

Rgds
Reinhard

zedlin

Everyone’s correct about using IAS and the three types of climbs. How heavy are you? You won’t get 210 all the way to FL250, especially if it’s heavy and hot. Try using pitch hold. At my airline we set the pitch for 5 degrees shortly after take off and it works great. Might have to lower the nose a bit once you get higher up, or you can set IAS once the plane hits 190kts when you’re in pitch hold, which should work good too.