Which 707's use Hushkits?

[anels9]

What modeled HJG 707's use stage III hushkits or have a unique engine/design?

[aerofoto - HJG Admin]

To answer your question fully/completely .... for the benefit of both yourself and everyone else too

There are 2 types of HUSH KIT configurations represented among the HJG B707 inventory .... and which apply to "some" B707-138B (not any of the 120B aircraft though), B707-320B ADVC (and not any the standard -320B aircraft though also), and B707-320C aircraft subjects "ONLY"

The differences are as follows ....

"THIS" image shows the NON-HUSH KIT equipped B707 engine nacelle .... note the standard/short engine intake sleeve portion on the front section of nacelle ....



"THIS" next image shows the "STAGE 2" (type) HUSH KIT equipped B707 engine nacelle .... note the lengthened engine intake sleeve portion on the front section of nacelle ....



The above modifications began to be applied to a lot of fan jet engined civil B707's from the late 1980's/early 1990's in order to meet more stringent airport noise regulations which began to take effect from this period.

And "THIS" final image shows the "STAGE 3" (type) HUSH KIT equipped B707 engine nacelle .... note that the engine nacelle has an entirely different shape which is similar to that of JT3D-3B and JT3D-7 engined DC8-62/63 type aircraft or JT8D-217/219 engined MDX type aircraft ....



There are numerous "STAGE 2" HUSK KIT equipped JT3D series examples of the B707-138B/-320B ADVC/-320C among the HJG B707 inventory .... and these are all clearly defined within the AIRCRAFT CFG/ADD TO AIRCRAFT texture data for each respective aircraft subject, so, the end user need to do nothing other than having the complete B707 type aircraft base pack/s installed .... and to correctly copy & paste the required FLTSIM data to each CFG file.

The same also applies in regard to the "STAGE 3" HUSH KIT equipped JT8D examples of the B707 too .... but .... there are "only 3 examples" of these very rare aircraft represented throughout the entire HJG B707 inventory. These particular aircraft subjects are as follows ....

1. B707-320B ADVC

LOWA LTD
2006 - N88ZL - 707-330B
Textures by Gary Carlson
Last Updated: 14 Jul 2006

2. B707-320C

AIR MEMPHIS
2004 - SU-AVZ - 707-336C
Textures by Gary Carlson
Last Updated: 12 Dec 2006

ISLAMIC REPUBLIC OF IRAN
2013 - EP-AJD - 707-339C
Textures by Rafael Perez.S
Last Updated: 02 Aug 2013

These are located within each of the above-stated aircraft downloads page sections

Mark C
AKL/NZ

[anels9]

Thank you for the detailed description mark. and what about military versions of the 707?

[aerofoto - HJG Admin]

None of those, that are currently offered by HJG, are S2HK or HK3 equipped aircraft .... so far as I can, imediately, recall .... although, I understand, the US military do, indeed, operate a number of JT8D-217/219 (or military equivalent) powered versions of these aircraft.

Mark C
AKL/NZ

[dutchman2]

Werent there several 707's that were actually re-engined with JT--209 / -217's (Lowa)?
I know Boeing did one with CFM-56's (you all have it here), but did they investigate the JT-8 path?
Did MDC ever consider the JT-8 as a re-engine possibility for the DC-8?

[aerofoto - HJG Admin]

As I mentioned above .... P&W JT8D-219 re-engined versions of civil B707-320B ADVC and -320C aircraft are quite "rare". Both the LOWA LTB and AIR MEMPHIS versions of these aircraft (also referenced above) are, probably, the best known examples among those that do/did exist. However .... I understand that during more recent times this engine type has also been fitted to some of the USAF military C135 TYPE aircraft inventory.

Only 1 civil B707 was ever fitted with CFM-56 turbofan engines .... to both test fly and certify the new engine back in 1979 (designated "B707-700 N707QT") .... but beyond this test/certification program .... this particular aircraft was re-engined with P&W JT3D engines and then sold to the Government Of Morocco, as a VIP configured B707-320C, during 1982. One of the old/original issues which came back to haunt BOEING in respect of its re-engining of the B707 with CFM turbofan engines was that of the B707 design itself .... in that these aircraft did not have the ground clearance that had been designed into the DC8 .... and is another factor in what limited the B707's stretch-ability throughout its production life (the DC8 had been designed, from the start, with stretching in mind, and which resulted in these aircraft having both superior ground clearance as well as a slight forward canter when sitting of the ground, and which naturally elevated the aircrafts rear fuselage). It meant that the CFM engines, on the B707 wing, hung very close to the ground .... increasing potential for nacelle strikes (particularly during cross-wind landings) and foreign object ingestion and resulting consequential damage. It's also probably one of the reasons why these engines, on most military C135 TYPE aircraft, lack thrust reversers. There were other issues too .... in that modification of the B707's wing structure (to support the CFM engines) .... and landing gear (in order to increase the aircrafts ground clearance) was an horrendously expensive procedure that few, if any, airlines were willing to entertain .... especially when B757 and B767 TYPE aircraft, of far superior performance and capability, were about to be launched, by BOEING, on the world civil aviation market.

So far as I'm aware .... the P&W JT8D TYPE engine was never a candidate among any of the DC8 re-engining conversions. CFM-56 turbofan re-engining of DC8-61, -62, and -73 aircraft commenced during the early 1980's and was completed by around 1986 .... with some 110 aircraft having been converted. More conversions might have been undertaken had the US government, apparently, not extended its civil aircraft noise compliance regulations .... "STAGE 2" by 1983 and then "STAGE 3" by 2000. Beyond the CFM re-engining program many DC8 operators simply fitted their DC8-50, -61, -62, and -63 aircraft with various types of Hush Kit which did not dramatically alter the shape of the engine nacelle .... unlike was the case in respect of these more obvious modifications as were applied to some B707-138B, -320B ADVC, and 320C aircraft. The JT8D re-engining program did not commence until around the late 1990's (by which time most of the still, then, non-compliant DC8's had either been converted or already withdrawn from service) .... if I'm not mistaken.

Mark C
AKL/NZ

[+mrfaosfx]

Precisely the information I needed to find those missing textures, your a life saver Mark.

[Dee Waldron - HJG]

According to Terry's book on the DC-8, McD did consider the JT8D on the Super-70 project. Ultimately, the CFM56 won and the rest is history.

[christrott]

Couple of things Mark on the 707 and the CFM56.

First, all of the US Navy E-6's are converted 707-320's and all have been converted to F108 (CFM56), so while not "strictly" civilian, they are not originally KC-135's (which had taller main gear legs than the 707), so in that sense, there has been more than 1 707 converted.

Second, the KC-135R does not have thrust reversers simply because the USAF brass felt that they were a maintenance item they didn't want to deal with since the KC-135s land at very light weights since they offload almost all of their fuel prior to returning. However, this had several problems.

This created a problem when the Air National Guard began receiving KC-135R's. This is because many of the ANG units are based at civilian airports. As such, their previous aircraft had been the KC-135E, which were equipped with thrust reversers as the TF33's (JT8D's) they had installed were from former American Airlines 707's that the USAF had purchased specifically for those engines for the KC-135E and as spares airframes for the E-3 fleet.

Then, when the KC-135R was refitted with roller floors for handling cargo and began to be utilized as part of AMC's airlift fleet in addition to refueling, the higher weights on landing meant that brakes were being used up faster (because you had to brake more heavily) and many smaller airfields were removed from the suitability list because they did not have sufficient runway available when the KC-135 was carrying cargo to safely handle them.

What almost caused the USAF to change course was when they went to upgrade the RC-135 and EC-135 fleet. However, they again ended up rejecting reversers and major changes in the fleet operations were required as these aircraft land at very high weights considering that most have had all their extra fuel tanks removed and their reconnaisance equipment is extremely heavy. As a result, only a small number of the RC-135 and EC-135 aircraft have been converted and is the sole reason the USAF E-3C fleet hasn't been modified as well as all 3 types use the TF33 with thrust reversers.

[garryrussell]

A few 707's were built with the CFM-66 as AWAC aircraft...RAF for one

Chris didn't they buy a load of various ex airline 707's for the fins and other parts...that would be in addition to the AAL aircraft you mention.

[christrott]

I'm pretty sure that was the same purchase. The AAL 707's donated their tails to the E-3 program and the engines to the C-135 program. The USAF wanted the TF33 for its entire C-135 fleet, but when the decision to begin conversion was made, Pratt had ended production of the engine and so they weren't able to get any new ones, so they bought the AAL aircraft. They had gotten lucky and bought a few C-135B's new with the TF33 installed, but those only made for a very small number of RC-135 aircraft versus the very large number of KC-135s in the fleet. When the supply of TF33's dried up, the 707-700 / F108 program came into being and resulted in the KC-135R and KC-135T.