In order to eliminate the problem of retardant from the MD-87 air tanker entering the tail-mounted engines, Erickson Aero Tanker is making a major modification to their tank system. The company is adding an external tank on the belly of their MD-87s. This tank will have an exit point for the retardant that is quite a bit lower than the previous spade opening that was virtually flush with the belly.
Chuck Rhodes, Maintenance Supervisor for Erickson Aero Tanker, told us that the new exit point is in clean air well below the slip stream. At that location, the company expects the air flow will carry the retardant straight back, and will not force it up onto the wings and into the engines as before.
After experiencing what Erickson called “intermittent engine surges when dropping [retardant at] high coverage levels”, they installed air deflectors in front of the exit points for the retardant. But since they are taking this extraordinary step of a major modification to the tanking system, apparently the deflectors were not as effective as they had hoped.
The air tankers will still have the internal tanks and the capacity will remain at 4,000 gallons. Mr. Rhodes said they will not carry a full load this year until the company becomes more familiar with the new system.
This modification will require that the company start over again with the approval process, which includes receiving a Supplemental Type Certificate from the FAA and certification from the Interagency AirTanker Board.
The two MD-87s on exclusive use contract were scheduled to begin their mandatory availability periods on June 5 and 10, but the start dates are being pushed back by weeks, if not months.
In other Erickson news, they have four MD-87s and one MD-83 parked at the Madras, Oregon airport that have been stripped of their engines and have not been converted to air tankers. (See the video below.) The MD-83 is being used for parts, while they expect the MD-87s will be converted into air tankers after the bugs are worked out in the tanking system.
Erickson also has DC-7s. Tanker 62, now located at Redmond, will likely work on an exclusive use contract with the Oregon Department of Forestry (ODF) from July into mid-September. Tanker 66 has the option to work on a call when needed basis with the ODF. Mr. Rhodes said the company hopes Tanker 60 will receive a contract with CAL FIRE.