Welcome Guest. Sign in or Signup

3 Answers

Multi engine slow flight speed

Asked by: 2430 views , , ,
Commercial Pilot

Hey folks - I wanted to get opinions on the commercial multi slow flight speed required to perform the maneuver.  Our school's Baron B55 manuevers checklist states that slow flight should be accomplished at 88-90 KIAS (+10 kts higher than Vmc, +20 kts higher than stall speed).  I always thought this was due to risk of engine failure below Vmc, if flying closer to where slow flight "should" be flown (i.e. +5-10 kts above stall speed).  Stall speed in the Baron is 68 kts, Vmc is 78 kts.  Instructors at the flight school differ on this, the ACS requires a speed where "any further increase in angle of attack, increase in load factor, or reduction in power, would result in a stall warning".  The B55 POH does not specify a slow flight speed.  But I completely understand why you would want to maneuver in slow flight above Vmc. 

So what does everyone else teach?  Slow flight below Vmc, or above Vmc for safety?

Thanks,

Adam

Ace Any FAA Written Test!
Actual FAA Questions / Free Lifetime Updates
The best explanations in the business
Fast, efficient study.
Pass Your Checkride With Confidence!
FAA Practical Test prep that reflects actual checkrides.
Any checkride: Airplane, Helicopter, Glider, etc.
Written and maintained by actual pilot examiners and master CFIs.
The World's Most Trusted eLogbook
Be Organized, Current, Professional, and Safe.
Highly customizable - for student pilots through pros.
Free Transition Service for users of other eLogs.
Our sincere thanks to pilots such as yourself who support AskACFI while helping themselves by using the awesome PC, Mac, iPhone/iPad, and Android aviation apps of our sponsors.

3 Answers



  1. Boston Air on May 04, 2020

    Great question. In my opinion, we shouldn’t teach students to fly at airspeeds below Vmc. They should instead be taught to respect the red line. The ACS does not take precedent over the AFM and manufacturer’s limitations. The one exception is the Vmc Demonstration. The key difference being that maneuver is for demonstration purposes only and serves as a powerful tool to convince pilots not to slow below Vmc for any reason. Interested to hear what others have to say.

    +1 Votes Thumb up 1 Votes Thumb down 0 Votes



  2. Russ Roslewski on May 04, 2020

    While we need to properly instill the fear of red line into our students, if you “never” fly below red line, how do you practice stalls?

    Remember, Vmc is only Vmc if you’re flying at the conditions that every multiengine student knows very well. Of these, the one we have immediate control over is power. If we’re only using 50% power, for example, the actual “Vmc” for those conditions is far lower than red line. Or, in a power-off stall, Vmc is effectively zero.

    The scenario that always concerns me the most regarding the red line is the power-on stalls. The ACS allows these to be done at reduced power, and for good reason. High AOA, lots of power, and slow airspeed require careful monitoring.

    +2 Votes Thumb up 2 Votes Thumb down 0 Votes



  3. Warren Webb Jr on May 10, 2020

    Slow flight needs to be just above the stall warning. I doubt 88-90 will pass the checkride. As Russ said you will be below Vmc doing stalls. But also what about an engine failure during that stall entry or a failure of the operating engine in the Vmc demo – need to be ready for it.

    0 Votes Thumb up 0 Votes Thumb down 0 Votes


The following terms have been auto-detected the question above and any answers or discussion provided. Click on a term to see its definition from the Dauntless Aviation JargonBuster Glossary.

Answer Question

Our sincere thanks to all who contribute constructively to this forum in answering flight training questions. If you are a flight instructor or represent a flight school / FBO offering flight instruction, you are welcome to include links to your site and related contact information as it pertains to offering local flight instruction in a specific geographic area. Additionally, direct links to FAA and related official government sources of information are welcome. However we thank you for your understanding that links to other sites or text that may be construed as explicit or implicit advertising of other business, sites, or goods/services are not permitted even if such links nominally are relevant to the question asked.