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ATPMBA 3rd May 2009 10:20

Cessna 421
 
Has anyone flown/used a Cessna 421 airplane. I'm interested in its realiablity, opertaing costs, maintenace issues. How do the passengers like them? How do you like them from a pilots point of view.

Tmbstory 3rd May 2009 19:07

Cessna 421 Golden Eagle
 
Atpmba:

I flew a Cessna 421B on VIP work in South East Asia between 1972 and 1980. A great piston engine aircraft, the geared propellers and resulting lower noise levels in the passenger cabin were often commented on in a favourable manner. The aircraft was very reliable,quite reasonable to maintain.

We changed the 421 for a C441 and then a Citation 550. For some years the passengers used to bring up the issue of the Cabin comfort of the 421B.

Hope this helps

Tmb

fernytickles 3rd May 2009 19:21

We operate a C421 C. If you don't want to carry a decent load and you don't want to get there too fast, then the 421 is your plane. Its nice to fly, but ours can't take more than 3 people with full fuel. Its TAS in the teens is around 200kts. I find it very slow to climb unless its very light and the temps are very cold. If the temps are very cold, then beware the engine shock cooling... keeping them engines warm involves a 200fpm descent rate in our WI winters.

Asides from all that, its a nice aeroplane :ouch:

plugster 3rd May 2009 20:36

Can't give you any numbers on the operating costs. I flew/fly a 421C with RAM engines, winglets and speedbrakes. It flies very stable, has a very comfy cabin and is less noisy that other a/c in its class. The engines ( the RAM ones) use close to no oil, run very smooth and can be flown lean of peak without problems. Cruises faster than a King Air 90 at high levels. Can be flown with takeoff power from takeoff to landing ( wouldn't do that though...bit costly), climbs like a rocket if you firewall everything. Spacious cockpit for a piston twin. Ours has air conditioning, very useful during summertime. No seperate heater to fail as heat comes from the turbos...
Landing gear has some issues, and if you reduce the MAP too much during the descent the turbos won't maintain cabin pressurization. Doesn't take crosswind too easy.
My guess is reliability depends on the installed avionics, proper maintenance, previous owners...
Hope this helps.

what next 4th May 2009 10:04

Good morning!


Has anyone flown/used a Cessna 421 airplane.
I have over 1.000 hours in 400 series Cessnas, most of them on the 421, but also some on the 404 (same engines) and the 414 (same cabin). During the nineties I have co-owned a 421 for 8 years that was employed commercially. I still fly occasionally on two 421s (one privately owned late model 421C and a 421B that is used for aerial work (hail prevention)).


I'm interested in its realiablity, opertaing costs, maintenace issues.
The reliability used to be good, but is deteriorating now as the fleet is aging. The last one was built in 1985 - that was 24 years ago! The engines (Continental GTSIO 520) are very powerful, but really pushed to the limit and therefore maybe the most delicate engines to be encountered in any contemorary GA aircraft. I have never heard of "gitsos" that reached their 1600 hour TBO (some variants have only 1200 hours!) without major maintenance. I have experienced myself all of these failures (but not all of them with "my own" aircraft that was only operated with one of the owners on board and was treated accordingly): cracked cylinders, cracked exhausts, turbocharger problems, cracked crancases, worn reduction gears, worn oil pumps, oil leakage from all possible locations.

The situation is worsening quickly as some engine parts (like crancases!) are not manufactured any more / or only in batches when sufficient demand exists. This means, that even "factory new" engines are made with old parts. A 404 that I used to fly got one of those "new" engines early this year and developed a crack in the crancase after less than 50 hours. This is covered by warranty of course, but it means several weeks of downtime.

From what I see, it is becoming more and more difficult to find maintenace organisations with sufficient experience on type. I have witnessed two gear collapses on the ground (one with a 421C on tow and the other with a 404 during takeoff roll), each of them after several unsuccessful attempts to solve hydraulic problems by different maintenance companies. Our own 421 had frequent hydraulic problems too (and it was only 12 years old when we got it - half the age of the newest one existing now). One big advantage of the "B" model over the "C" is the electrically operated gear that seems to create far less trouble.

For the rest (electrics and avionics) it really all depends on the experience of the maintenance company. Spare parts are rare or nonexistent so they must be able to repair many items themselves. We once flew for six months without the autopilot working because that was the time it took to find a replacement part (over 10 years ago, much worse now! The private 421 I fly every now and then was grounded for three month because they could not find a replacement oil pump).
The petrol operated "Janitrol" heater (contrary to what another poster has written here, the heater is really needed because the hot air from the turbochargers is only sufficiently warm in low-level summer operations) is also a troublesome piece of equipment. I have spent quite a few hours in C421s at temperatures below freezing with fogged-up windshields and no way to get the heater going... I know of one commercial 414 operator who had a lawsuit going against his maintenace for several months because of their repeated failures to fix the heater.

I would reckon (luckily, I haven't had to pay a maintenance bill myself for a long time now) that the hourly maintenance cost of a 421 is in the same order of magnitude (if not higher!) than that of the Citations I fly now. As reliability is concerned, the hail prevention 421 that I have flown occasionally during the last couple of years needed one maintenance event per flight (!) during that period. To it's defense I must say that it is stored outside and only flies every two or three weeks on average. And when it flies, it gets a rough beating due to the nature of its work... (it really is not the right aircraft for the job).


How do the passengers like them?
As others already said, it is very quiet and quite comfortable for a piston twin. But for most passengers it is just another "puddle jumper" with propellers on it, so all they really care for is to get out of it as quickly as possible.


How do you like them from a pilots point of view.
Now this is the nice thing about it :) It really is a wonderful aeroplane to fly. Lovely harmonised controls, very stable, powerfull and very capable when operated within its limits. A late model 421C with trailing link gear and vortex generators can be flown into (and out of - as long as both engines are running) amazingly short fields. But it is not very fast in the cruise (around 190 KTAS with maintenance-cost friendly powersetting). The older 421Bs are 10 to 20 knots faster in the cruise (they are lighter and have a different wing) but they need more runway and more pilot skill to be landed softly. Single engine performance is marginal at MTOM as in most light twins. I have had one engine failure (turbocharger broken off the exhaust manifold) shortly after rotation and with 4 POB and 2/3 full tank we got between 200 and 300 ft/min climb rate. From that day on, this is my personal weight limit for the 421. And no commercial operation ever again.

So if you really want a 421 (I know, they can be found incredibly cheap now): Find an experienced maintenance organisation first (also for electrics and avionics)! Take them along when you inspect/buy the aircaft. Believe them, when the say "no", even if the airplane seems to look nice. There have been lots and lots and lots of expensive ADs over the last 20 years. Make sure they have all been complied with. Make a long demonstration/test flight. Check everyting including de-icing. If anything does not work, don't buy. For example a replacement heated windscreen (they often do not work in older airctaft) costs more then 20.000 $ / Euros - if you can find one. Remember: no heated windscreen - no flight into known icing.

Get an experienced pilot/instructor to familiarise you with the aircraft.
Operate the engines as if they were raw eggs: No firewalling of the levers ever (spare that red-line for emergencies when you need it). Stay away from the manifold-pressure red line as far as you can. Whenever safeley possible, we did (and do) limited power takeoffs. End-of-green-arc is usually sufficient (32.5 inches as opposed to the 39 red-line setting). Dont climb at max rate, but at a good speed for cooling (like 130 knots). Sacrifice 5 or 10 knots cruise speed in favour of engine life. Always lean the engines but don't lean to peak or above.

Descend slowly: There are no cowl flaps, the airflow thruogh the nacelles is always the same - on the ground (idling in summer in Italy you will reach red line temperatures and red line oil pressure after about 10 minutes!) - during climb (again, during summer in Italy steep max. cont. power climbs will quickly bring everything above the red lines) - and during descent, when it cools much too fast. Do only fly as high as necessary. Above FL 180 the climb rate is so poor that you really need to fly a very long distance to justify the extra expense in fuel and engine wear.

Plan your descent early so that you can stay within 500 ... 1000 ft/min. Reduce power by about 1 in every minute to keep the engines hot. A ham-fisted colleague of mine once cracked 4 cylinders during a single quick descent after a maintenance test flight. Never shut down an engine during trainig or checkrides. Our mechanic (who owns a 421 himself) once told me that the price an inflight shutdown/restart is about 1000 Euros.

And most important: Never ever borrow of hire a 421 to anybody. Not even your closest friend. Unless you are also on board and can prevent him from wrecking the engines.

Greetings, Max

SNS3Guppy 4th May 2009 12:44

Several weeks ago I was providing some instruction in a Cessna 421 B to a new hire in a charter operation. About twenty minutes into the flight, we experienced a depressurization when the left windshield blew out, taking the glareshield and top of the instrument panel with it.

In the weeks that have followed, I learned that a number of these incidents have occurred, nearly identical in nature. The new replacement windshields are considerably thicker, and must be custom drilled and fitted to the airplane. The original factory windscreens weren't that way, however. They were made by an outside vendor, predrilled, and the screw holes weren't necessarily centered. We found that the screws were corroded, that they impinged on the windshield, and over time the expansion and contraction most likely lead to cracking which caused the failure under pressure (it was rather explosive).

What Next's comments are accurate regarding the airplane.

The Cessna 421 has marginally better performance than a Cessna 414...but neither one has stellar single engine performance. With full fuel there's a very small payload. Three adults and enough fuel to go very far will max the airplane out...and at those weights, single engine performance is very low.

The geared engines are a known quantity. Very easy to damage. Properly flown, they're great...but if the airplane is going to be flown by multiple pilots, watch out. Someone who gets in there with poor habits such as letting the slipstream drive the engine instead of maintaining positive engine power, is going to do some damage. It may not show up when they're in the airplane, but soon thereafter the engine will be making metal.

L-Band 4th May 2009 19:55

OK!
I have read with great interest your comments regarding the Cessna 421 and 404. I worked for a very experienced Cessna dealer for a log time. We sold many 421, 414, 404 and operated this aircraft with no problem. You do get the fair wear and tear items but otherwise that is all. The main problem was the operation of the GTSIO 520 engines these did not stand up to abuse, you had to 'nurse' them and they were fine.
Don't you think that the understanding of these aircraft (and many more) is no longer available and getting things repaired is almost impossible. This is because the eng who looked after your aircraft is not there anymore, retired, got out!

I was bought up (since 1967) with Cessna/Piper/Beechcraft when airplanes were airplanes, with Avionics/electrics/autopilot and flight system and spares for these aircraft are no problem

Just PM me

Regards L:ok:

hawker750 5th May 2009 11:43

L-Band
Did you work for the same Leeds based Cessna outfit where we got our 3 x 404's maintained back in the 80's? Chief engineer called Brian something. He could tune those engines to perfection. He advised only to buy Teledyne re-manufactured engines. They were expenseive but we NEVER pulled a cylinder in 7 years of operation and ALWAYS got 1920 hours from the engines 1600 + 20%. The trick was to use only about 1 or 2 power changes for the entire flight, difficul, but if planned properly worked out well and never go below 20 inches untill on the ground.
The "gitsos" are great engines if you know how to handle them, the main weakness I seem to remember was weak starter clutches that should be changed at the first sign of slipping before bits fall off it inside the engine.

L-Band 5th May 2009 14:49

hawker750
Yep that is the one!
Knew these aircraft inside out and there are still some of the ex engineers around.
The starter clutches were a problem, but look at that big engine they had to turn over when cold!!

Were you based at Gatwick?

Best regards
L

transilvana 5th May 2009 15:28

Those turbos are tricky, the 1" descend rule is the best to follow to keep them for a long time.

Tmbstory 5th May 2009 16:09

Cessna 421B
 
Some of the above posts seem to point to the engines as a problem but I did not find that. In fact in 8 years of operation I had no unscheduled engine changes.A few magneto failures happened from time to time.

We had good maintenace and I did the majority of the Flying.

A very good aircraft.

Tmb

hawker750 6th May 2009 16:44

L Band
Yes Gatwick was our base but most flying out of Aberdeen. One year we did 1200 hours on one aircraft and it never went wrong, not until we got it back to Leeds that is!
I long for that sound. Two Gitsos at 1600 rpm/30 inches, sweet!

gordon field 8th May 2009 21:03

L-Band and Hawker 750
The engineer was Brian Sharp, great guy, totally trustworthy, kept us all flying safely and sadly missed. Boss man Ernie Crabtree passed away some years ago.

EASA means more white coated 'quality assurance' inspectors many who do not have and will never acquire the indepth practical experience he and others had.

The 404s and 421s were and still are great flying aircraft but we must all remember that like us they are all getting older and higher time there are just not the current experienced pilots around to convert younger pilots on to type. Lots of words of wisdom from many experienced pilots.

I preferred to fly the 421B with the flexible wing and tip tanks in turbulence. Wet wing 421C has better systems (less pumps and fuel cells), 1980+ trailing link 421C smoother to land.

Critical parts will become even harder to come by over next few years as pool dries up.

Happy landings

Jetset41 8th May 2009 21:11

Cessna 421
 
Speaking as a 30 yrs experience engineer, my 1st tyoe rating was on the engine and airframe of the 421.

I spent 10 years working on these, most of the above comments are true to a point, but i need to address a few,
Heaters, if you knew what you were doing, there was no problem, easy access for a piston aircraft [try an aztec].
The u/c was pretty bomb proof apart from the torque link cracking and the odd vescalized strut internals galling up.
The poor old engine, the best sounding piston of modern times, 375 hp on full song static ground run, brill, but as has been said, if the jocks were over zealous with the load lever too quickly especially in descent, well we got paid more to fix it.
We did have a few engine changes [unscheduled] bilboa, oporto and at base, don't mention oporto to Roy Man, we nearly didn't make it out alive.

All in all I still love those babies, but just don't volunteer to change the flap cables and rig them, man that was a lovely job.

Have flown in several variants 421B, 421C and a stol 421C's.

jetset41:D

Bravohotel 15th May 2009 02:04

I remember Brian Sharp and the rest of the NA crew,great bunch of guys,I was doing my OE in 1979 and during my 6 month stay in the UK I got a job I had a mate who worked there,who had done his OE in New Zealand the year before,I went back for the summer the following year.Ernie was an interesting boss,I remember doing a flight with him in the 441 and onroute he over flew a RAF base at low level the CO was very p..... off ,but it was a Sunday morning.
Years later I went to work in Papua New Guinea (still do) and one outfit I worked for had 2 404s and with the right drivers & engineers the GITSOs would go to TBO,but it only took one ham fisted pilot to stuff that up....Brian

rogerg 15th May 2009 09:12

I flew G.BBOB for some years and the only additional comment is that we had to add prist to the fuel to stop the injectors icing up on long trips.
Did enjoy it tho.

gordon field 16th May 2009 20:11

It isn't the actual injectors that ice up but the fuel distributor manifold on top of the engine. I think that in the 1980 Model 421C they started to run an oil pipeline through this manifold and that cured the problem on that aircraft whenso modified. A lot of pilots don't read the POH about adding alcohol.

411A 17th May 2009 04:22


It isn't the actual injectors that ice up but the fuel distributor manifold on top of the engine. I think that in the 1980 Model 421C they started to run an oil pipeline through this manifold and that cured the problem on that aircraft whenso modified. A lot of pilots don't read the POH about adding alcohol.
Yup.

GTSIO engines are realistically one of the most reliable opposed 6-cylinder piston engines TCM have ever produced, IF......you can keep pilots from ham-fisting the throttles on a regular basis.
I personally know one owner whom has run his GTSIO engines to 1800 hours, and still going.

Expressflight 17th May 2009 06:56

Stop it ...... you're making me feel all nostalgic.

Tmbstory 17th May 2009 07:38

Cessna 421B
 
Expressflight:

It sure does!

Tmb


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