enginehistory.org

[jschauer]

Great news!
JOINT NEWS RELEASE
COMMEMORATIVE AIR FORCE HEADQUARTERS
Midland, TX
CAVANAUGH FLIGHT MUSEUM CONTACT: Autumn Esparza
Addison, TX Director of Membership and
Public Relations

FOR IMMEDIATE RELEASE

Jim Cavanaugh to Sponsor CAF B-29 Bomber - FIFI

The Cavanaugh Flight Museum ("CFM") and the Commemorative Air Force ("CAF") announced today a Cooperative Agreement that will put the world's only airworthy B-29 back in the air. Jim Cavanaugh has pledged $1.2 million sponsorship for the re-engine project of FIFI, the CAF's world famous B-29. "This sponsorship, together with additional donations from CAF members, should go a long way towards completing the project of putting FIFI back in the air again," said Stephan Brown, President / CEO of the CAF. "Fundraising for FIFI by the CAF will continue, as we still have other restoration maintenance to perform, but Jim Cavanaugh's generosity will get us a long way down that track," Brown continued. Cavanaugh is the main financial support for the CFM and has been a long time benefactor of warbird projects and the CAF. "The B-29 played such a significant role in history that it is important that this airplane be preserved. Because of my close relationship with the CAF, I felt the need to get FIFI flying again," said Cavanaugh.

Additionally, the B-29/B-24 Squadron Staff of the CAF, which has been assigned with the responsibility of operating the B-29 and the B-24A, voted unanimously to base these two airplanes at the CFM. According to Lyn Fite, CAF B-29 / B-24 Squadron Leader, "Up to now, these aircraft were based out of Midland, but this unit move will be beneficial to the Squadron in many ways," said Fite. "We will reside in Addison Texas, at the CFM, for six months, while we perform annual maintenance and we will tour on behalf of the CAF, by our crews, for the other six months." Steve Sheridan Director of Maintenance of CFM exclaimed, "We have the facilities and resources to assist the volunteers of the B-29/B24 and look forward to helping in any way we can." According to Doug Jeanes, Director of the CFM, visitors of the museum will be able to view this spectacular aircraft during its annual maintenance, at no additional cost.

The Cavanaugh Flight Museum is a non-profit 501(c)(3) educational organization devoted to promoting aviation studies and to perpetuating America's aviation heritage; the museum fulfills its mission by restoring, operating, maintaining and displaying historically-significant, vintage aircraft, and by collecting materials related to the history of aviation.

The Commemorative Air Force is a nonprofit aviation association dedicated to Honoring American Military Aviation, through Flight, Exhibition and Remembrance. The CAF has more than 8000 members within 75 units worldwide, flying and restoring 171 vintage Warbirds.

For more information of the Commemorative Air Force or the Cavanaugh Flight Museum, go to www.commemorativeairforce.org or www.cavanaughflightmuseum.com

[gwhite]

John - this is wonderful news..!! Will you still be the flight engineer when FiFi gets airborne again? Also, what engines; -57s or -26WDs?

[jschauer]

Yes I'll still be FE, Lord willing. The engines will be a combination of -26 and -95. The -26 rear case fits the engine mounts with no modifications. We have about eight -95 engines from C-119s that were manufactured in the early 60s. What we will have is basically the same racing engines that the boys in Reno use, but we will use much less power. The exhaust system will have to be manufactured from scratch, as you know the old -57 front cylinder row exhausted to the front and the rear cylinders to the rear. The new engines will exhaust all cylindrs to the rear. I'm not sure if we will have a low tension magneto system or the high tension system, or if we'll be carbureted or injected.

[jjuutinen]

I have wondered that given the overheating problems with the B-29, why wasn´t ADI used in it?

How high are the TO weights you have used with FIFI? I have noted that at MTOW the B-29 had by far poorest TO performance of all heavy bombers (over 50% greater TO distances than e.g. comparably (MTOW) loaded Lancaster II).

[jschauer]

ADI isn't used to cool an engine, it is used only as an anti-detonation agent during high power settings. Any airplane that had it only had about a two minute supply, enough for takeoff. The cooling problem was mainly limited to the earlier military career. The engine baffling was poorly designed along with the cylinder heads and induction system. The crews would takeoff and imediately climb to altitude with a heavy load causing the engines to overheat in the long climb. Later during the war the learning curve on how to operate the engines improved vastly. The crews would take off then cruise for hours burning the fuel down and then do a step climb with intermediate cruises to allow the engine to cool again. The only cooling problem we run into regularly is the engines getting too hot on the ground, once we get airborne they cool right down to normal.

The military regularly used 140,000 lbs. as a MTOW. Our CAF regulations limit us to 110,000 lbs. Thats filling it with gas, 14 people, baggage, tools, and PX stuff. TO distance is about 3,000 feet or so. Another CAF regulation is we have to have 6,000 of runway as a safety margin.

[jjuutinen]

If ADI is used at constant boost, the CHTs will be lower compared to the dry power at the SAME boost. And e.g. the Bf 109K-4 had an ADI supply for over 20 minutes, the F4U for over 10 minutes.

[jjuutinen]

At 140,000 lbs or so the handbook values are 5000+ ft ground run and over 7000 ft to clear 50 ft. The Lancaster II manages (at about 70,000 TOW, practically an overload condition) to get airborne in less than 2500 ft while clearing 50 ft after about 4500 ft.

[jschauer]

Amazing that the TO figures are similar. The empty weight of FIFI is about 65,000, with a light fuel load we get airborne in about the same distance as the Lanc. On any of our flights we will be arborne at about 110 mph. The pilot will hold the nose level and accelerate to about 140 mph before starting to climb, for minimum control speed and engine cooling. The ADI is actuated by high throttle position (manifold pressure), so of course you will have a higher CHT, which brings the engine closer to detonation where you need ADI. You will also be using a higher RPM also which means more firing cycles in the engine per moment of time causing higher engine temps too. All of the transport aircraft I know of have only about a two minute supply strictly for TO. I know nothing about the fighters.

[jjuutinen]

Schauer, if you use ADI at constant rpm and MAP, the CHTs will be lower than without ADI. There is no technical reason why ADI couldn´t be used at the same boost. In fact, there were plans to use ADI to lower long range cruising consumption provided a method of recovering the water from the exhaust could be developed.

BTW, at 70,000-75,000 lbs you would have lower wing loading plus nearly 30% better power loading than the Lanc II so you should have shorter TO runs.

[jschauer]

You're rapidly getting above my engineering knowlege. Why would you want to carry that extra water, which weights about 3 lbs. more that gas for a marginal improvment in performance during cruise? How much water are we talking about? At cruise the CHTs are well within the normal range without water. I would think the extra weight would off-set any performance gain. I'm not trying to argue....

[jjuutinen]

You are not arguing:) The key point on the cruising application would have been the development of a method to recover the water by condensing it from the exhaust. Had the method been devised, it would have been used in service.

I highly recommend you to obtain this book: "Report of Joint Fighter Conference, NAS Patuxent River 16-23 October 1944" edited by Francis Dean and published by Schiffer. The book is basically the verbatim transcript of the conference discussions. This is essential for any serious enthusiast´s bookshelf.

The book does mention that cruising use of ADI as well.

[jschauer]

Bear with me.

Using ADI in cruise you would be able to lower RPM and using high boost (standard procedure to lower fuel consumption), using a lower octane fuel (more cost effective), ultimately to reduce fuel consumption?

By manually leaning the mixture past peak EGT the CHT will drop anyway. It just seems to me it was an engineering project to justify their job function. I'm thinking of it from the mechanic and flight engineering point of view and all I see is a nightmare for maintenance.

[jjuutinen]

Yes, the second para is correct. I disagree on the third for I don´t think the addition of ADI would make the B-29 a maintenance nightmare if it wasn´t that already!

[jschauer]

The ADI system isn't what I meant by being difficult to maintain. I think the nightmare would be the system to recover the water from the exhaust. Geez, what an engineering nighmare that would be!

I think the last B-29s used by the USAF did have ADI, not sure of that though.

[jjuutinen]

I beg to disagree. A condenser is a very simple device after all.

By the way, have you read William Wolf´s B-29 book? I mean that 360-page tome. Excepting a serious hiccup in the propeller section, a very good book.