Name a certificated aircraft that was so popular that at one time the manufacturer was producing one complete finished airworthy (except needing fueling) aircraft every 10 minutes. There was a quirk about this aircraft that was unique re a certain flight requirement. This aircraft also flew under two completely different nomenclatures although identical in basic construction. And, finally-there was a wing spar material change in late production. (I am not making this up!)

1. Aircraft manufacturer name.

2, Aircraft model name/names?

3. A certain flight requirement quirk?

4. Late production wing spar material?

10 days later

I'm assuming that this is a non wartime production aircraft?

Not sure how to answer this-don't assume anything. And that becomes a solution leading clue.

With over 250 views and no right answers, here are the answers-which may surprise.

1. Piper Aircraft Corporation in Lock Haven, Pennsylvania.

2. Piper J-3 Cub, briefly Piper O-59, then Piper L-4 Grasshopper. O for Observation, L for Liaison.

3. Seating was two in tandem, and the quirk was the aircraft was required to be flown from the back seat when in solo operation.

4. Late model production changed from wood wing spars to aluminum.

The venerable civilian Piper J-3 Cub was offered with three engine choices; most popular was the Continental C65 of 65 Hp, next was the Lycoming L65 and least bought-the Franklin F65. I have only one photo of a Piper J-3 Cub (that I am aware of) that was originally engined with the Franklin. That aircraft with floats has had an engine upgrade change and can be viewed in my Featured Aircraft section here-or enter N7174A for a Piper J3F-65 upgraded. The O and L versions only differed from the civil J-3 in added fenestration to better serve their wartime roles.

There are several engine upgrades by STC's for the J-3 Piper Cub; one of the popular upgrades is to the Continental C-90 of 90 Hp. Military engine mechanics loved the O-59/L-4 Grasshopper because it was so easy to maintain.

From 1931 until 1935 Piper financed the Taylor Cub. Production started of the Piper Cub in 1939, and was reintroduced after WWII. Prewar production had J-3s coming off the assembly line every 10 minutes for a time. Most Americans back in the day referred to most any small aircraft seen in flight as a Piper Cub, it was so well known. J-3 production ended in 1947. That same year the PA-11 Cub Special was introduced which allowed the pilot to fly from the front seat. Offered then was either a 65 Hp or 90 Hp engine.

I thank all who were again puzzled by this quiz feature.

14 days later

Doug, I have 5 J3F-65's in my photos. Three were at AirVenture this year. But I didn't look at them if they still had their Franklin engines or not. I've also see two J3P's. N20280 & N21561. They have Lenape 3 cylinder radial engines.

Thanks friend Timothy,

It is difficult over time to establish true aircraft data when a choice of engines were originally offered, or power upgraded by STC and with ownership changes the official FAA Aircraft Registration of present exact aircraft data may be flawed. It costs time, documentation and money to correct even obvious errors and the FAA tends to dissuade present aircraft owners from doing so.

It is best if possible to look closely at obvious marks of change, such as a Lycoming engine with changed cowling on a Beech Bonanza-40 of those were done by STC, and I have photographed just one of the 40. See N36PC with a turbo Lycoming.

I believe a J-3 Cub if still in registry with an original Franklin engine is a rarity. Congrats on your observations and photos, which may need further study.

Doug