"Republic R-46? " Topic

"Okay – it's a bogus designation, based on the Navy practice of designating a research aircraft with its identifier for the manufacturer and the manufacturer's model number of the design, e.g. Douglas D-558-1 Skystreak. (Also see link In this case, it was Republic's AP-46, the Air Force's XF-84H informally known as Thunderscreech, a flying test bed for supersonic propellers. While the model number is correct, an R for Republic is conjecture on my part. Neither it nor its predecessor, Seversky, was apparently ever assigned a manufacturer's designation by the Navy.*

I first read of the Navy's prospective involvement in the program in the 3 May 1954 issue of Aviation week, which stated that the XF-84H was to fly in August. It also stated "the Air Force will use the plane to check supersonic propeller characteristics" and, of more interest to me, after being "fitted with another type Aeroproducts propeller, it will also undergo Navy carrier trials"…"

link

Full article here
link

Amicalement
Armand

The blogger misunderstands Navy nomenclature. The "D" in D-588 was not added by the Navy, it was part of the company designation (like DC-3 and DB-8). In the case of Army/Air Force models used for test only the original designation was retained, XF-84H in this case. If the aircraft was merely on loan, it would even retain its serial number rather than be issued a BuNo.

The interesting point was that even after jet aircraft were in production propeller aircraft were still being used and tested. The reason is that till about mid 1950 jet engines had a 5 hour to service time. Not good on an aircraft that had to fly for over 5 hours. That is one of the reasons why the B-36 Peacemaker had 6 propeller engines and later had 2 and then 4 jet engines added (the jet engines were shut down most of the time).

The XF-84H was a turboprop job. The idea was to try and increase fuel efficiency.

One big reason to use a turboprop is fuel economy. Even with today's super-high-bypass turbofans, they suck fuel like a frat boy doing a keg stand. And the early jets sucked fuel like an entire fraternity at the keg.

A second reason is to get power NOW. Push the power lever forward and the props immediately bite more air. No lag.