[BUG] - 250 KTS Below 10k not honoured when CRZ level is below 10k

[KJA1582]

Describe the bug

Cruising at a crz level below 10k does not restrict ECON speed to 250kts

Steps to reproduce

CRZ below 10k

Expected behaviour

ECON speed should be capped to 250kts below 10k

Evidence

Simulator

Microsoft Flight Simulator 2020 (MSFS)

Crash

No

Phase of flight

Cruise

Altitude

8000ft

Departure

EDDM

Arrival

EDDM

Cruise level

FL080

ZFW

112.7t

CG

25.9%

Fuel

13.8t

Cost index

80

Route

EDDM to EDDM, No SID, No STAR, ILS26L OTT Transition

Location

N/A

Agreement

• [X] Yes

[turbofandude]

Is it capped to 250 by FMS SPD (i.e. the AP) or would ECON itself in the PERF page show under 250?

[KJA1582]

That's a good question, one an SME ought to check (I've not found any mentionings of what it does in the docs I have, a sub 10k CRZ is rather rare).

Either way, it should definitevly cap at 250 or Min clean like it does on CLB.

[GR1MMly]

Adding discussion from discord to here. Will have to do some more digging in FMS logic when I have the time to see if I can dig up a better answer, but from the hip the speed restrictions (250/10000) are in the CLB and DES modes. I'm not aware of a cruise "limit" (outside structural/configuration limits) that can be set in CRZ.

A pitfall of cruising below 10k very well may be that you are the speed control. At least until I can locate data otherwise.

[KJA1582]

Fair point, but it'd be the only AC I know of (within the sim) that would do so (unless I completely forgot the 737/777/320 behaviour which very well might be)