This is an excerpt from a report made to the Aviation Safety Reporting System. The narrative is written by the pilot, rather than FAA or NTSB officials. To maintain anonymity, many details, such as aircraft model or airport, are often scrubbed from the reports.
Narrative 1
The Piper PA-44 Seminole was flown from ZZZ to ZZZ1 to do two MEI check rides.
When running up for the first check ride flight the mags failed the mag drop. After leaning and running the engine for a minute the mags then passed.
Moving on to the idle check the left engine dropped to the mid 500s and ran really rough. Rechecked the mags and idled again and the engine went to 480 rpm and was still running rough.
Decided to abort the flight and to call maintenance. Called maintenance and they said that if we go run at 1300 rpm we will burn the fuel out of the servo regulator and it should be just fine to continue. So we went and did that and it idled above 600 rpm and was stable.
Proceeded with the check ride and everything was normal.
The second applicant (Student B) went to go fly a hot plane and the DPE pulled mixture on takeoff and put it back in and the engine did not start back up. They taxied off with one engine and did not try to restart it. They discontinued and the MEI and myself (Student A) thought the plane was fine to fly back to ZZZ.
On the flight back in cruise the MEI and I decided to switch seats because he did not need the multi time. We switched seats and nothing happened and we landed safely in ZZZ.
At work the following day we found out that we broke SOP by flying the plane without maintenance looking at it.
Narrative 2
While flying two MEI candidates to a check ride, we made it safely to the check ride airport.
My candidate passed her ground.
Upon running up, the left engine of the twin seemed rough. She returned to the ramp as she did not want to do a check ride with a rough run-up engine. We called maintenance back at headquarters. Maintenance told us it was probably due to there being a little extra fuel in the engine cylinder, and that it would run perfectly the next morning, but wouldn’t do us any good now.
We asked what to do now, to which our mechanic advised to do another run-up and see how things went.
My student and I got into the Seminole and did another run-up. No issues were witnessed during the second run-up.
I then called my boss, who said to continue the check rides.
While we did the run-up, Student B did his ground. Student A then did her flight portion with no problems reported. Student B then decided to go fly.
Prior to takeoff and prior to half of VMC, the DPE pulled the left engine’s mixture. Student B responded appropriately and idled both engines, and stopped straight ahead. The left engine then quit. Student B returned to the ramp.
Student B debated about continuing the check ride. He was nervous about the left engine failing. We concluded that it was vapor lock that caused the left engine to quit. He finally decided to discontinue the flight portion.
We asked the DPE his thoughts. DPE said it was safe to fly back.
We decided to fly back to our originating airport. We conducted a thorough preflight. We performed a hot start and both engines started up. We did a thorough run-up to which both engines were acting normal. We returned back to our originating airport without issue.
Primary Problem: Aircraft
ACN: 2143716
