enginehistory.org

[avasko]

As a once upon a timke a line mechanic starting in fifties, I only worked civil types, almost all four engined but never amiltary aircraft except their radar-toting/transport derivatives. I am amazed at the skill and determination people taking old, rusted big round engines and restore them to things of beauty and, make them RUNNERS. Short prop, magnificant trailers to mount them and go to airshows..And yet when I see them, they look like naked ladies.,
You see, when I rolled my toolbox out I did not see an engine like tat. I saw a smooth aluminum shell, cowl flaps the size of elephan's ears and stainless steel aft of exhausts so you could get to the accessory section. If you were lucky, it might be a Lockheed with their aft firewall doors in the wheelwell and outbd nacelles.
Which gets me back to cowling. I am looking 15+ feet up at a DC4/6/7 outboard engine. I wish to change a spark plug on an upper rear cylinder. DACO cowls on pistons came in three large, heavu pieces of tin. Left and right sides, top cowl. On the bottom seam, funky latches requiring wrench much beloved by DACO as they usewd them on DC8's. Up ladder, long row of DZUS fasteners on DC4/Airlocs on 6 and 7. Unfasten them, wrestle with cowl panel (try it in a hard wind) and tenderly lay in on mat/wood, etc/ Repeat for other side. This leaves top cowl which you wrestle with atop 15-ft stand.. Want tyo change an injection pump/generator. etc. on rear accessory case, sorry but only steel side planels on the side.
Excepting the original C-69/L-049Connies, Lockheed cowls were all hinged and attached to nacelle. Hooked latches on the cowling seam and side. Disconnect single point L & R cowl flaps which then went up with the side pices. Push up in top center inlet cowl, use rods to hold up.Bottom pies (two) with oil cooler inlet drops down.
Which aircraft would you prefer to work on? Please vote for your favorite engine installation. Do not nominate B-36 or, worst of all, Bristol Brabizon with coupled Centaurus radials buried in wing. Military, civil, open to all, and yes, Lindbergh engine was easier for it had no ring cowling.

[rwahlgren]

The cowling for a C-97, is fairly light weight, an easy one person operation if you know how to do it. I notice on photos of the C-97 that the Berlin airlift historical foundation has, that someone installed some handles on the cowling, I think those were on the plane before BAHF got the plane. I just use a strap.
http://www.spiritoffreedom.org/

Look at the little handle near the top of the engine cowling.
At 0:44 seconds mark.

https://www.youtube.com/watch?v=ITo4n9UlsGM



Shows engine removal

http://www.proplinerinfoexchange.com/1-other_news.htm#OCT30-2021

[avasko]

I remember talking to you about the C-97 at Floyd Bennett Field. Magnificent job getting it airworthy. We were talking of four bladed HS props. The ones on DC-7 had quite heavy prop domes and, using engine oil, required desludging of domes. Probably similar to C-97 ones. Did the C-97 have a seperate prop oil installation to avoid sludge?
I never had to uncowled / coweled B.377 or the military ones. Having to cover two extra rows of cylinders must have added weight.
The L-1049 / L-1649 had the best as they were hinged to the nacelle and the cowl flaps went up with them. The Boeing installatioon keeps the cowl flaps in place. That makes working the rear row aft side difficult. Douglas same problem especially on DC-7 with its PRT]'s.
Douglas used a forward ring attached sll around the front cyliners. It had a rubber lined slot all around. Inside the cowl panels were a ring of spades. When installing, cowl had to be positioned so spadfes fit into slots.. This positioned it so cowl could not move fwd or aft.
Murphy's Law came in effect. Came into work one night and there was a customer's DC-6B with an engine front of cowl disintegrated and prop trailing edge not being all threre. The top piece of cowling is installed first and determines the fore / aft positon of all the others. The only indication of a misaligned was at aft end of shell which slid over firewall. In this case there would be exposed about one inch of primer colored nacelle. If cowl was properly installed, it covered that.
Aircraft departed. Apparently there is a low air pressure at cowl entrance. Sucked the whole cowl forward and into prop.. Bad result. It caused an FAA AD must do DACO SB to install a locator bolt on side of cowl. If cowl not lined up, bolt receptacle is out of line. Good idea but one more pain in decowling engine. <Image>

Another picture of an engine change on B377. Pretty sophisticated rig. <Image>

Access to accessory section. From the picture I I would classify it as a tough installation to work. Changing generator which are quite heavy must have been difficult. With electric prop deicinf there would be an alternator too adding to fun. <Image>

Boeing B-50, half-brother to Stratocruiser, with awesome Curtiss Electric four-bladed props. Believe there's some difference in turbo installation between the two aircraft. <Image>

[rwahlgren]