What would be the advantage of a Puller vs. Pusher configuration on Embraer's new Turboprop?

Question

Embraer recently teased a turboprop aircraft with aft-mounted, open rotor engines. Why would this aircraft not use a pusher configuration?

The reasons that are frequently stated as a benefit for a wing-mounted, pull configuration (e.g. avoidance of disturbed flow from the wings, blown lift over the wings, control surface effectiveness, etc.) would not apply here. To the contrary, it seems to me that re-energizing the exhaust/wake of the engine and maybe to some extent the fuselage would have a beneficial effect.

One possible reason could be that Embraer would like to use an existing engine. In that case turning it around would point the exhaust forward and the intake backwards. That, however, also seems to be a solved problem: the MQ-9 uses the Honeywell TPE331-10GD turboprop engine, which is designed for a pull configuration. Another might be ground clearance during rotation.

Answer 1

1. Pusher configurations often run into clearance issues. The landing gear is usually further forward of the prop, and while taking off, or flaring to land, the prop has to have enough clearance to avoid prop strike. Usually this is solved by bigger landing gear (more mass) or placing the engine higher (thrust misalignment + usually more mass) but ultimately both solutions lead to the ability to use a larger radius propeller in puller configuration, and the bigger your prop, the better efficiency, so why not use the pusher configuration?

2. You mentioned an engine that can be used for pusher prop configuration, but, when it comes to mass production and corporate supplier relations - that engine might not be available to Embraer. For instance - Honeywell has an exclusive contract with, say, Boeing or Airbus for that engine. Or - Honeywell cannot produce enough of those engines to fulfill a contract with Embraer, and they are perhaps phasing the engine out for a variety of reasons, so they have no wish to increase production.

3. Engine cost. Continuation of pt.2 - most turboprop engines are designed to be pullers. This means that they will have a decent amount of common components. Turboprops for pushers are not as common, so there would be a larger amount of unique components, which would drive up design and production costs, as well as maintenance and sales costs.