Those Crazy Sweedish Dash Drivers! (gear collapse)

[Sig]

One poster already told us that the Dash has 2 electric backup pumps.

And that poster explained that they run on 3-phase variable AC generators, that only turn dynamically while the engines are in fact running. Ever get juice from your alternator while the car's turned off?

Have hydraulics set failsafe to standby and shut the engines down. Two things will happen. you will use the standby to come to a stop on all three gear.

We're talking about the DeHavilland Dash 8, right?

 

[WSurf]

What if your F/O screwed up and only shutdown and feathered one of them or one was slower to feather then the other and you had gotten assymetrical drag causing severe yaw in the critical phase of landing?

You are looking to add problems to an already bad situation.

Good Point, yet you would still be able to control the airplane! I think you would be more worried about one going into Beta then one feathing before the other.

Hell, just reach up grab both T Handles and pull! Fuel will be shut off, Hydralics Off, and the fire bottles would be ready for you on the ground!!

Funny, imagine telling your 250hr FO thats never shot a approach to mins to pull both the handles!!!

 

[The_Russian]

And that poster explained that they run on 3-phase variable AC generators, that only turn dynamically while the engines are in fact running. Ever get juice from your alternator while the car's turned off?

We're talking about the DeHavilland Dash 8, right?

You have an inverter on a standby bus, right?

 

[Sig]

You have an inverter on a standby bus, right?

Standby bus? Inverter?

Okay, if it takes roughly 87 amps of current, three phases of AC, and 115V of potential coming from either of two engine-driven alternators (this is the term they use in the MX Tech manual to my right), how many flapjacks does it take to shingle a doghouse?

Seriously, lady. You have no idea what you're talking about.

 

[lineflyer1]

That's my last worry. My crew is properly briefed when things go wrong, and I insist on clear communication. One prop would not feather slow enough to cause an asymetrical load. That would require a control or mechanical failure. Most props fail to feather anyway, and the following fuel shutoff would feather the prop.

Stop throwing hypotheticals. They wont help the discussion. There will always be a hypothetical to counter your hypothetical. It is best to stick to the staight facts.

So you have an understanding that most props fail to feather, so you have a relativly good chance that one out the two will not feather properly according to your thought process, so you feather and shutdown both engines in the critical phase of landing anyway?

BTW, by the time the engines are actually shutdown and the engine speed reduces enough to allow the oil pressure to reduce low enough to allow the props to feather in your scenerio you've run out of time!

 

[The_Russian]

Standby bus? Inverter?

Okay, if it takes roughly 87 amps of current, three phases of AC, and 115V of potential coming from either of two engine-driven alternators (this is the term they use in the MX Tech manual to my right), how many flapjacks does it take to shingle a doghouse?

Seriously, lady. You have no idea what you're talking about.

Are you going to answer the question?

 

[Sig]

Are you going to answer the question?

As soon as you ask one within the domain of the DHC-8 systems, of course I will.

 

[The_Russian]

So you have an understanding that most props fail to feather, so you have a relativly good chance that one out the two will not feather properly according to your thought process, so you feather and shutdown both engines in the critical phase of landing anyway?

BTW, by the time the engines are actually shutdown and the engine speed reduces enough to allow the oil pressure to reduce low enough to allow the props to feather in your scenerio you've run out of time!

Your posts do not apply to the topic. Stick to the situation at hand. How often do props not feather when commanded? Give me a break. All four of the turboprops I have flown feather in one second or less, consistantly, when commanded. Three of those failed to feather, the EMB-120 does not. The 120 didn't fail me, neither did my FO.

 

[WSurf]

This is the most fun I have had in a long time!!!

Give'em Hell Russian!!!

 

[DashTrash400]

Hey Russian! You wanna know what it's like to land a DHC8 with no hydraulics? It's been done at Horizon before following a massive engine fire. You can check out the results here:

http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001213X25438&key=1

The airplane was totalled when it hit the jetway and several people were hurt, one critically. It's by the grace of God and the skill of the FA in evacuating everyone that nobody was killed.

Here's what you lose when both engines are shut down on a Q400:

-All AC Power, including the Standby Hyd Pump.
-DC Generators
-EPCU (electronic power control unit) goes into emergency mode, leaving a few DC-powered gadgets usable. APU does not work in air (WOW switch).
-Landing Gear
-Spoilers
-Steering
-Emergency Brake except via accumulator good for about three pumps as previous poster noted.
-Normal Braking
-Antiskid
-Flaps
-PTU
-All Rudder
-2/3 of Elevator PCUs

Not to mention that a Q400 gets a big portion of its lift from propwash over the wing & flaps and landing without power results in a scary hard landing, and using pitch to get the oh-so-soft landing you demand would break the tail off the airplane!

Now go back to telling us how to fly a B1900 you've bought a job on, and shut the he|| up on telling us how to fly Q400s/DHC8s when you know nothing about the airplane.

 

[The_Russian]

As soon as you ask one within the domain of the DHC-8 systems, of course I will.

Do you have a hydraulic pump which can be power though an inverter, from a battery, on a standby system or mode?

I.E.:
A 28vdc to a bus through an ac inverter to one or more pumps which can power one or more hyd systems in the aircraft.

 

[Sig]

This is the most fun I have had in a long time!!!

Give'em Hell Russian!!!

Quit eggin' her on, B-Dub! This is kinda fun, though.

 

[Sig]

Hey Russian!

Now go back to telling us how to fly a B1900 you've bought a job on, and shut the he|| up on telling us how to fly Q400s/DHC8s when you know nothing about the airplane.

There isn't enough bourbon in Kentucky to get me to her level of arrogant BS-ery, to the point where I'd be correcting an old ASA pilot on the Bro! I'd be ashamed of myself.

 

[Singlecoil]

Listen to what you are being told, Russian. The Dash uses 115v variable frequency (3 phase) AC to run the standby hydraulic pumps. This power comes from the AC generators which generates electricity when the prop is turning (it is on the prop reduction gearbox). The inverter produces 115v FIXED frequency AC to power some of the avionics. It cannot power the standby hyd pumps. Different bus, different power. No worky worky.

The main hyd pumps are also on the prop reduction gearbox. You can close a gear door if maintenance left one open on a dash by walking up to the right prop and spinning it in the direction of travel for about 5 turns.

So now we have demonstrated to you that with no props spinning on a dash, you get no main hyd pumps, no AC generator, and therefore, no standby hyd pumps. The rudder has a standby pressure unit, which was designed after the N819PH accident described above, so you would have a rudder, but no spoilers, no nosewheel steering, emergency brakes only (with a handle you have never used before) NO ANTISKID, and probably something else I can't remember from 5 years ago.

You didn't have all the facts when you made your "shut 'em both down" comment. Now you have a couple more facts.

 

[Sig]

Do you have a hydraulic pump which can be power though an inverter, from a battery, on a standby system or mode?

I.E.:
A 28vdc to a bus through an ac inverter to one or more pumps which can power one or more hyd systems in the aircraft.

For literally the FOURTH time: NO.

 

[Wiggums]

Now go back to telling us how to fly a B1900 you've bought a job on

Did she PFT? I always gave her the benefit of doubt on that one.

 

[The_Russian]

Lunch, I'll be back.

 

[Sig]

Lunch, I'll be back.

Might I suggest "Crow?"

 

[Singlecoil]

Horizon must be cancelling flights to tell the crews to shut off both the engines if they have a red light on the gear indication. LOL.

Horizon cancels 113 flights

By BRAD WONG
P-I REPORTER
Thousands of Horizon Air customers will have to rebook or find new flights immediately, following Wednesday's announcement that 19 turboprop aircraft will be pulled from service for inspections.
The precautionary inspections will affect at least 113 flights Wednesday, said Laurie Hohisel, a Horizon spokeswoman. Passengers should be prepared for cancellations throughout the week.
The Seattle-based carrier is encouraging customers to check its Web site, www.horizonair.com, or call 800-547-9308 for assistance. The carrier also might book passengers on other airlines.
The inspections of the Canadian-made Bombardier Aerospace Q400 airplane follow two cases in Europe on Sunday in which SAS-affiliated Q400s had landing gear failures, Hohisel said.
Affected Horizon flights include ones from Seattle to Spokane, Portland, Reno and Bellingham.
Horizon, which is owned by Alaska Air, will use aircraft from Alaska Airlines for 13 flights, said Caroline Boren, an Alaska spokeswoman.
Hohisel does not believe those flights will be able to replace all of the cancellations. "But it will help," she said.
The Horizon inspections are scheduled to begin as soon as possible and will be conducted by company mechanics.
But the flight delays could affect more than 8,300 passengers. Each Q400 holds between 74 to 76 passengers.
The aircraft manufacturer asked Horizon to look at Q400s that had over 10,000 cycles, which means a departure and landing. Horizon has operated those planes since 2001.
But the announcement will not affect 14 Q400s.
Each day, the carrier operates about 480 flights. Of that number, about 240 are flown on Q400 aircraft.

Outbound flights from Sea-Tac canceled Wednesday

• 2484 to Bellingham, scheduled to depart 7:50 a.m.
• 2488 to Bellingham, scheduled to depart 1:10 p.m.
• 2492 to Bellingham, scheduled to depart 6:30 p.m.
• 2402 to Boise, scheduled to depart 8:40 a.m.
• 2326 to Boise, scheduled to depart 2:20 p.m.
• 2398 to Boise, scheduled to depart 5:25 p.m.
• 2326 to Bozeman, scheduled to depart 2:20 p.m.
• 2478 to Calgary, scheduled to depart 9:25 p.m.
• 2318 to Edmonton, scheduled to depart 9:05 p.m.
• 2295 to Eugene, scheduled to depart 7:45 a.m.
• 2299 to Eugene, scheduled to depart 6:25 p.m.
• 2326 to Idaho Falls, scheduled to depart 2:20 p.m.
• 2282 to Kalispell, scheduled to depart 10:10 a.m.
• 2461 to Medford, scheduled to depart 10:30 p.m.
• 2332 to Pasco, scheduled to depart 8:05 a.m.
• 2338 to Pasco, scheduled to depart 4 p.m.
• 2429 to Portland, scheduled to depart 8 a.m.
• 2263 to Portland, scheduled to depart 11 a.m.
• 2241 to Portland, scheduled to depart 12 p.m.
• 2455 to Portland, scheduled to depart 2 p.m.
• 2326 to Portland, scheduled to depart 2:20 p.m.
• 2495 to Portland, scheduled to depart 5 p.m.
• 2459 to Portland, scheduled to depart 5:30 p.m.
• 2229 to Portland, scheduled to depart 8 p.m.
• 2275 to Redmond, scheduled to depart 2:10 p.m.
• 2255 to Reno, scheduled to depart 2:57 p.m.
• 2475 to Santa Rosa, scheduled to depart 1:35 p.m.
• 2378 to Spokane, scheduled to depart 9 a.m.
• 2368 to Spokane, scheduled to depart 10 a.m.
• 2438 to Spokane, scheduled to depart 1 p.m.
• 2376 to Spokane, scheduled to depart 2 p.m.
• 2292 to Spokane, scheduled to depart 7 p.m.
• 2358 to Spokane, scheduled to depart 8 p.m.
• 2276 to Vancouver, scheduled to depart 12:15 p.m.
• 2386 to Victoria, scheduled to depart 11 p.m.

Incoming flights to Sea-Tac canceled Wednesday

• 2485 from Bellingham, scheduled to arrive 9:40 a.m.
• 2489 from Bellingham, scheduled to arrive 3:05 p.m.
• 2493 from Bellingham, scheduled to arrive 8:20 p.m.
• 2411 from Billings, scheduled to arrive 7:25 a.m.
• 2269 from Boise, scheduled to arrive 8 a.m.
• 2237 from Boise, scheduled to arrive 12:30 p.m.
• 2337 from Boise, scheduled to arrive 5:55 p.m.
• 2399 from Boise, scheduled to arrive 8:50 p.m.
• 2311 from Bozeman, scheduled to arrive 1:05 p.m.
• 2473 from Calgary, scheduled to arrive 7:30 a.m.
• 2296 from Eugene, scheduled to arrive 10:25 a.m.
• 2298 from Eugene, scheduled to arrive 8:59 p.m.
• 2283 from Kalispell, scheduled to arrive 1:30 p.m.
• 2458 from Medford, scheduled to arrive 1:40 p.m.
• 2331 from Pasco, scheduled to arrive 10:25 a.m.
• 2335 from Pasco, scheduled to arrive 6:25 p.m.
• 2244 from Portland, scheduled to arrive 6:55 a.m.
• 2266 from Portland, scheduled to arrive 8:50 a.m.
• 2262 from Portland, scheduled to arrive 12:20 p.m.
• 2462 from Portland, scheduled to arrive 4:20 p.m.
• 2270 from Portland, scheduled to arrive 5:50 p.m.
• 2496 from Portland, scheduled to arrive 7:25 p.m.
• 2274 from Redmond, scheduled to arrive 4:55 p.m.
• 2256 from Reno, scheduled to arrive 7:20 p.m.
• 2474 from Santa Rosa, scheduled to arrive 12:50 p.m.
• 2327 from Spokane, scheduled to arrive 11:35 a.m.
• 2367 from Spokane, scheduled to arrive 12:35 p.m.
• 2439 from Spokane, scheduled to arrive 3:35 p.m.
• 2377 from Spokane, scheduled to arrive 4:31 p.m.
• 2293 from Spokane, scheduled to arrive 9:35 p.m.
• 2277 from Vancouver, scheduled to arrive 2:40 p.m.
• 2387 from Victoria, scheduled to arrive 6:55 a.m.

 

[Wiggums]

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